clozapine and Basal-Ganglia-Diseases

clozapine has been researched along with Basal-Ganglia-Diseases* in 135 studies

Reviews

42 review(s) available for clozapine and Basal-Ganglia-Diseases

ArticleYear
Second-generation antipsychotics and extrapyramidal adverse effects.
    BioMed research international, 2014, Volume: 2014

    Antipsychotic-induced extrapyramidal adverse effects are well recognized in the context of first-generation antipsychotic drugs. However, the introduction of second-generation antipsychotics, with atypical mechanism of action, especially lower dopamine receptors affinity, was met with great expectations among clinicians regarding their potentially lower propensity to cause extrapyramidal syndrome. This review gives a brief summary of the recent literature relevant to second-generation antipsychotics and extrapyramidal syndrome. Numerous studies have examined the incidence and severity of extrapyramidal syndrome with first- and second-generation antipsychotics. The majority of these studies clearly indicate that extrapyramidal syndrome does occur with second-generation agents, though in lower rates in comparison with first generation. Risk factors are the choice of a particular second-generation agent (with clozapine carrying the lowest risk and risperidone the highest), high doses, history of previous extrapyramidal symptoms, and comorbidity. Also, in comparative studies, the choice of a first-generation comparator significantly influences the results. Extrapyramidal syndrome remains clinically important even in the era of second-generation antipsychotics. The incidence and severity of extrapyramidal syndrome differ amongst these antipsychotics, but the fact is that these drugs have not lived up to the expectation regarding their tolerability.

    Topics: Antipsychotic Agents; Basal Ganglia Diseases; Benzodiazepines; Clozapine; Drug-Related Side Effects and Adverse Reactions; Humans; Receptors, Dopamine D2; Schizophrenia

2014
Clozapine: more side effects but still the best antipsychotic.
    The Journal of clinical psychiatry, 2010, Volume: 71, Issue:8

    Topics: Antipsychotic Agents; Basal Ganglia Diseases; Clozapine; Drug Discovery; Drug Monitoring; Drug Resistance; Humans; Psychotic Disorders; Schizophrenia; Treatment Outcome

2010
Are second generation antipsychotics a distinct class?
    Journal of psychiatric practice, 2008, Volume: 14, Issue:4

    Second generation antipsychotic medications have become synonymous with "atypicality." To support the clinical lore of equivalent efficacy with reduced risk of extrapyramidal symptoms, clinical trials have overwhelmingly chosen a high-potency first-generation antipsychotic (e.g., haloperidol) as a comparator. Very few clinical trials have compared a second-generation antipsychotic with a low- or mid-potency first-generation antipsychotic medication.. We identified eight completed, published, double-blind, randomized clinical trials that compared a second-generation antipsychotic with a low- or mid-potency first-generation antipsychotic and reviewed outcome measures for efficacy and extrapyramidal symptoms; 1,241 patients were represented in these eight trials.. Although data are very limited, mid- and low-potency first-generation antipsychotics show efficacy and extrapyramidal side effects that are comparable to those of second-generation antipsychotics.. Aside from clozapine, first-generation and second-generation antipsychotics represent a diverse group of medications that have heterogenous receptor profiles and side effects but comparable clinical efficacy and potential to cause extrapyramidal symptoms. Clinicians may provide better treatment for patients by considering the unique pharmacological and side-effect profile of each particular antipsychotic independent of its classification as a first- or second-generation agent.

    Topics: Antipsychotic Agents; Basal Ganglia Diseases; Clozapine; Cognition Disorders; Haloperidol; Humans; Quality of Life; Schizophrenia

2008
A clinical paradigm of delusions of parasitosis.
    Journal of the American Academy of Dermatology, 2008, Volume: 59, Issue:4

    Topics: Aged; Antipsychotic Agents; Aripiprazole; Basal Ganglia Diseases; Benzodiazepines; Clozapine; Diagnosis, Differential; Female; Humans; Metabolic Syndrome; Middle Aged; Olanzapine; Pain; Patient Compliance; Peripheral Nervous System Diseases; Piperazines; Quinolones; Schizophrenia, Paranoid; Skin Diseases, Parasitic; Sleep Wake Disorders

2008
Efficacy and tolerability of second-generation antipsychotics in children and adolescents with schizophrenia.
    Schizophrenia bulletin, 2008, Volume: 34, Issue:1

    Early-onset schizophrenia-spectrum (EOSS) disorders (onset of psychotic symptoms before 18 years of age) represent a severe variant associated with significant chronic functional impairment and poor response to antipsychotic treatment. All drugs with proven antipsychotic effects block dopamine D(2) receptors to some degree. The ongoing development of the dopamine and other neurotransmitter receptor systems during childhood and adolescence may affect clinical response and susceptibility to side effects in youth. A literature search was conducted of clinical trials of antipsychotics in children and adolescents with EOSS disorders between 1980 and 2007 from the Medline database, reference lists, and conference proceedings. Trials were limited to double-blind studies of duration of 4 or more weeks that included 15 or more patients. Ten clinical trials were identified. Antipsychotic medications were consistently found to reduce the severity of psychotic symptoms in children and adolescents when compared with placebo. The superiority of clozapine has been now demonstrated relative to haloperidol, standard-dose olanzapine, and "high-dose" olanzapine for EOSS disorders. However, limited comparative data are available regarding whether there are differences among the remaining second-generation antipsychotics (SGAs) in clinical effectiveness. The available data from short-term studies suggest that youth might be more sensitive than adults to developing antipsychotic-related adverse side effects (eg, extrapyramidal side effects, sedation, prolactin elevation, weight gain). In addition, preliminary data suggest that SGA use can lead to the development of diabetes in some youth, a disease which itself carries with it significant morbidity and mortality. Such a substantial risk points to the urgent need to develop therapeutic strategies to prevent and/or mitigate weight gain and diabetes early in the course of treatment in this population.

    Topics: Antipsychotic Agents; Basal Ganglia Diseases; Benzodiazepines; Clozapine; Disorders of Excessive Somnolence; Haloperidol; Humans; Olanzapine; Prolactin; Schizophrenia, Childhood; Treatment Outcome; Weight Gain

2008
[The use of atypical antipsychotics in the long-term care of schizophrenia].
    L'Encephale, 2006, Volume: 32 Pt 3

    Topics: Amisulpride; Antipsychotic Agents; Aripiprazole; Basal Ganglia Diseases; Benzodiazepines; Clozapine; Cognition Disorders; Drug Tolerance; Dyskinesia, Drug-Induced; Haloperidol; Humans; Olanzapine; Piperazines; Quinolones; Risperidone; Schizophrenia; Sulpiride; Time Factors

2006
The role of second-generation antipsychotic monotherapy in the rapid control of acute bipolar mania.
    The Journal of clinical psychiatry, 2005, Volume: 66 Suppl 3

    A key goal of the pharmacologic treatment of acute bipolar mania is rapid symptom improvement. Medications commonly used to attain this goal include lithium, several anticonvulsants, and both first- and second-generation antipsychotics. Second-generation antipsychotics, which are associated with substantially lower rates of extrapyramidal side effects than first-generation agents, are becoming a mainstay in the treatment of acute mania. Although their efficacy appears to be comparable, second-generation antipsychotics may differ in time to onset and in their side effect profiles. Therefore, selecting a second-generation antipsychotic requires consideration of how an agent's efficacy, onset of action, and adverse events profile influence its appropriateness for each patient.

    Topics: Acute Disease; Anticonvulsants; Antipsychotic Agents; Aripiprazole; Basal Ganglia Diseases; Benzodiazepines; Bipolar Disorder; Clozapine; Dibenzothiazepines; Double-Blind Method; Humans; Lithium; Olanzapine; Piperazines; Placebos; Quetiapine Fumarate; Quinolones; Randomized Controlled Trials as Topic; Risperidone; Treatment Outcome

2005
Toxicology and overdose of atypical antipsychotic medications in children: does newer necessarily mean safer?
    Current opinion in pediatrics, 2005, Volume: 17, Issue:2

    Atypical antipsychotic medications (second-generation antipsychotics) have been increasingly used in the treatment of a number of psychotic disorders since their introduction in 1988, with the newest medication introduced in 2002. Justification for their use includes claims of equal or improved antipsychotic activity over first-generation antipsychotics, increased tolerability, and decreased side effects. However, there are still significant adverse effects and toxicities with this class of medications. Toxicologic exposures and fatalities associated with atypical antipsychotics continue to increase in the United States, with 32,422 exposures and 72 deaths in 2003. There have also been Food and Drug Administration warnings in the past year about how some atypical antipsychotics have been marketed to minimize the potentially fatal risks and claiming superior safety to other atypical antipsychotics without adequate substantiation, indicating the toxicologic potential of these agents may be underestimated.. Continued research to evaluate adverse effects and tolerability of atypical antipsychotics compared with first-generation antipsychotics and each other is reviewed. This article also reviews the pharmacodynamics, pharmacokinetics, and drug interactions with these medications. New therapeutic monitoring recommendations for this class of medications have also been proposed. Finally, clinical toxicity in overdose and management are reviewed.. While new atypical antipsychotic medications may have a safer therapeutic and overdose profile than first-generation antipsychotic medications, many adverse and toxic effects still need to be considered in therapeutic monitoring and overdose management.

    Topics: Antipsychotic Agents; Aripiprazole; Basal Ganglia Diseases; Benzodiazepines; Cardiomyopathies; Child; Clozapine; Diabetes Mellitus; Dibenzothiazepines; Drug Interactions; Drug Overdose; Dry Eye Syndromes; Humans; Hyperlipidemias; Hypotension; Olanzapine; Piperazines; Quetiapine Fumarate; Quinolones; Risperidone; Seizures; Thiazoles

2005
Lewy body dementia: the litmus test for neuroleptic sensitivity and extrapyramidal symptoms.
    The Journal of clinical psychiatry, 2004, Volume: 65 Suppl 11

    Lewy body dementia, also referred to as dementia with Lewy bodies (DLB), is a neurodegenerative disorder now considered to be the second most common cause of dementia after Alzheimer's disease. Postmortem findings suggest that DLB accounts for 20% to 34% of all dementia cases and is often underdiagnosed. Salient features of DLB include fluctuations in cognition, perceptual abnormalities (e.g., visual hallucinations), and mild parkinsonism. Other symptoms include frequent falls, nighttime agitation, and depression. DLB symptomatology can be partly explained by the extensive destruction of dopaminergic and acetylcholinergic pathways caused by neurodegeneration. For this reason, DLB patients are especially vulnerable to the antidopaminergic and anticholinergic actions of most conventional antipsychotics, which makes treatment of the psychotic symptoms of DLB extremely difficult. Patients are particularly sensitive to developing extrapyramidal symptoms (EPS) and also to the potentially fatal complication of neuroleptic sensitivity, which affects approximately 50% of DLB patients. Therefore, a need exists for antipsychotic drugs with less propensity to induce EPS and reduced affinity for dopamine and acetylcholine receptors. Here we review studies evaluating the efficacy and tolerability of atypical antipsychotics for the treatment of psychoses associated with DLB. Olanzapine appears to be poorly tolerated, and risperidone has been associated with high risk of neuroleptic malignant syndrome. Clozapine use remains controversial because of its potent anticholinergic action and risk of agranulocytosis. Quetiapine has been shown to reduce psychiatric manifestations of DLB without causing neuroleptic sensitivity or increasing EPS. Hence, quetiapine is an attractive candidate for the treatment of psychoses in DLB and other dementias.

    Topics: Aged; Antipsychotic Agents; Basal Ganglia Diseases; Benzodiazepines; Clozapine; Controlled Clinical Trials as Topic; Dibenzothiazepines; Humans; Lewy Body Disease; Olanzapine; Parkinson Disease; Psychotic Disorders; Quetiapine Fumarate; Risperidone; Treatment Outcome

2004
Physical health monitoring of patients with schizophrenia.
    The American journal of psychiatry, 2004, Volume: 161, Issue:8

    Schizophrenia is associated with several chronic physical illnesses and a shorter life expectancy, compared with life expectancy in the general population. One approach to improving the health of patients with schizophrenia is to improve the monitoring of physical health that occurs in psychiatric settings. The authors discuss a consensus panel's recommendations for improving the physical health monitoring of patients with schizophrenia who are treated in outpatient settings.. A consensus meeting including psychiatric and other medical experts assembled on October 17-18, 2002, to evaluate the existing literature and to develop recommendations for physical health monitoring of patients with schizophrenia. Conference participants reviewed the literature in the following areas: 1) weight gain and obesity; 2) diabetes; 3) hyperlipidemia; 4) prolongation of the QT interval on the ECG; 5) prolactin elevation and related sexual side effects; 6) extrapyramidal side effects, akathisia, and tardive dyskinesia; 7) cataracts; and 8) myocarditis. Experts for each topic area formulated monitoring recommendations that were discussed by all of the participants until a consensus was reached.. Consensus recommendations included regular monitoring of body mass index, plasma glucose level, lipid profiles, and signs of prolactin elevation or sexual dysfunction. Information from monitoring should guide the selection of antipsychotic agents. Specific recommendations were made for cardiac monitoring of patients who receive medications associated with QT interval prolongation, including thioridazine, mesoridazine, and ziprasidone, and for monitoring for signs of myocarditis in patients treated with clozapine. Patients who receive both first- and second-generation antipsychotic medications should be examined for extrapyramidal symptoms and tardive dyskinesia. Patients with schizophrenia should receive regular visual examinations.. The conference participants recommended that mental health care providers perform physical health monitoring that typically occurs in primary care settings for their patients who do not receive physical health monitoring in those settings. This change in usual practice is recommended on the basis of the conference participants' belief that this additional monitoring will result in the earlier detection of common, serious risk factors that could, without detection and intervention, contribute to impaired health of patients with schizophrenia.

    Topics: Adult; Antipsychotic Agents; Basal Ganglia Diseases; Cataract; Clozapine; Diabetes Mellitus, Type 2; Health Status; Humans; Hyperlipidemias; Hyperprolactinemia; Long QT Syndrome; Monitoring, Physiologic; Myocarditis; Obesity; Practice Guidelines as Topic; Schizophrenia; Sexual Dysfunctions, Psychological; Weight Gain

2004
Clozapine, quetiapine and olanzapine among addicted schizophrenic patients: towards testable hypotheses.
    International clinical psychopharmacology, 2003, Volume: 18, Issue:3

    Although life prevalence of substance use disorders among patients with schizophrenia is close to 50%, few studies have been carried out to date to identify an integrated pharmacological treatment for this comorbidity. So far, the most promising results, that we report here, have been obtained with clozapine. To a lesser extent, quetiapine and olanzapine, both clozapine analogues, have also shown promising results. Further to these observations, the present paper critically reviews the advantages associated with clozapine, quetiapine and olanzapine, and their relevance to the treatment of addiction among schizophrenic patients. Six characteristics seem to distinguish clozapine, quetiapine and olanzapine from the first-generation antipsychotics: (1) acting preferentially on the reward system, these second-generation antipsychotics (mainly clozapine and quetiapine) induce almost no extrapyramidal symptoms; (2) quickly dissociating from D(2), theses drugs (mainly clozapine and quetiapine) seem not to induce dysphoria, unlike conventional antipsychotics like haloperidol;(3) these drugs (mainly clozapine) seem more effective in the treatment of negative symptoms than conventional antipsychotics; (4) because of a diversified activity on several serotoninergic and noradrenergic receptors, these drugs positively alter mood, which does not seem to be the case with conventional antipsychotics, except for flupenthixol; (5) these drugs have a positive impact on cognition, which is not the case with the first-generation antipsychotics; (6) unlike conventional antipsychotics, these drugs seem to have a moderate affinity for 5-HT(3), the receptor on which ondansetron, an anti-craving medication, acts.

    Topics: Affect; Antipsychotic Agents; Basal Ganglia Diseases; Benzodiazepines; Clozapine; Cognition; Comorbidity; Dibenzothiazepines; Drug Therapy, Combination; Humans; Olanzapine; Pirenzepine; Quetiapine Fumarate; Receptors, Serotonin; Receptors, Serotonin, 5-HT3; Schizophrenia; Substance-Related Disorders; Treatment Outcome

2003
Pharmacological approaches to the management of schizophrenia.
    The Medical journal of Australia, 2003, 05-05, Volume: 178, Issue:S9

    Pharmacological treatment remains the mainstay of the management of schizophrenia. Older, "typical" antipsychotics carry a significant burden of side effects, notably extrapyramidal and neurocognitive side effects. Newer, "atypical" agents carry a lower risk of extrapyramidal side effects. They appear to have added benefit for treating negative and cognitive symptoms of schizophrenia, and hence can enhance the quality of life of some patients. The choice of particular agents for individual patients requires a balancing of efficacy and side effects. Medication is only one element of what should be an individualised comprehensive treatment plan for people with schizophrenia.

    Topics: Amisulpride; Antipsychotic Agents; Basal Ganglia Diseases; Benzodiazepines; Clozapine; Dibenzothiazepines; Humans; Olanzapine; Pirenzepine; Quetiapine Fumarate; Risperidone; Schizophrenia; Sulpiride

2003
An integrated analysis of acute treatment-emergent extrapyramidal syndrome in patients with schizophrenia during olanzapine clinical trials: comparisons with placebo, haloperidol, risperidone, or clozapine.
    The Journal of clinical psychiatry, 2003, Volume: 64, Issue:8

    The frequency and severity of extrapyramidal syndrome (EPS) were evaluated in patients with DSM-III or DSM-IV schizophrenia in the acute phase (- 8 weeks) of randomized, double-blind, controlled trials from the integrated olanzapine clinical trial database.. This retrospective analysis included 23 clinical trials and 4611 patients from November 11, 1991, through July 31, 2001. Incidences of dystonic, parkinsonian, and akathisia events were compared using treatment-emergent adverse-event data. Categorical analyses of Simpson-Angus Scale and Barnes Akathisia Scale (BAS) scores, use of anticholinergic medications, and baseline-to-endpoint changes in Simpson-Angus Scale and BAS scores were compared.. A significantly smaller percentage of olanzapine-treated patients experienced dystonic events than did haloperidol- (p <.001) or risperidone-treated patients (p =.047). A significantly greater percentage of haloperidol-treated patients experienced parkinsonian (p <.001) and akathisia (p <.001) events than did olanzapine-treated patients. Categorical analysis of Simpson-Angus Scale scores showed significantly more haloperidol- (p <.001) or risperidone-treated patients (p =.004) developed parkinsonism than did olanzapine-treated patients. Olanzapine-treated patients experienced significantly greater reductions in Simpson-Angus Scale scores than did haloperidol- (p <.001), risperidone- (p <.001), or clozapine-treated (p =.032) patients. Categorical analysis of BAS scores showed significantly more haloperidol-treated patients experienced treatment-emergent akathisia versus olanzapine-treated patients (p <.001). Significantly greater reductions in BAS scores were experienced during olanzapine treatment versus placebo (p =.007), haloperidol (p <.001), and risperidone (p =.004) treatments. A significantly smaller percentage of olanzapine-treated patients received anticholinergic medications compared with that of haloperidol- (p <.001) or risperidone-treated patients (p =.018). Compared with that in olanzapine-treated patients, the duration of anticholinergic cotreatment was significantly longer among haloperidol- (p <.001) or risperidone-treated patients (p =.040) and significantly shorter among clozapine-treated patients (p =.021).. This analysis of available data from olanzapine clinical trials lends additional support to olanzapine's favorable EPS profile.

    Topics: Acute Disease; Adult; Antipsychotic Agents; Basal Ganglia Diseases; Benzodiazepines; Cholinergic Antagonists; Clozapine; Double-Blind Method; Female; Haloperidol; Humans; Male; Olanzapine; Pirenzepine; Placebos; Randomized Controlled Trials as Topic; Retrospective Studies; Risperidone; Schizophrenia

2003
Broad therapeutic uses of atypical antipsychotic medications.
    Biological psychiatry, 2001, Dec-01, Volume: 50, Issue:11

    The atypical antipsychotics have a low incidence of extrapyramidal side effects (EPS), have improved tardive dyskinesia profiles, and have a broad range of therapeutic efficacy. These agents offer important therapeutic advantages that extend beyond their initial regulatory approval in several conditions and patient groups. The use of atypical antipsychotics is most relevant in the treatment of mood disorders, where these medications are being used increasingly for acute mood stabilization and in patients who are resistant to other treatments. Similar circumstances and clinical advantages pertain to the use of atypical antipsychotics in the treatment of behavioral disturbances in patients with dementia and in the management of personality disorders-both circumstances where conventional antipsychotics were initially poorly tolerated because of EPS. The low incidence of EPS associated with atypical antipsychotics is highly beneficial in several neuropsychiatric conditions. The extent to which endocrine and metabolic dysregulations associated with atypical antipsychotics will influence antipsychotics' role remains to be determined. As therapeutic opportunities evolve and diversify, atypical antipsychotics, because of favorable adverse-effect profiles, will have enhanced patient tolerability and use in nonpsychiatric conditions.

    Topics: Antipsychotic Agents; Basal Ganglia Diseases; Benzodiazepines; Child; Child Development Disorders, Pervasive; Clozapine; Dementia; Dibenzothiazepines; Humans; Mood Disorders; Olanzapine; Personality Disorders; Pirenzepine; Quetiapine Fumarate; Risperidone

2001
Atypical antipsychotics: are some more atypical than others?
    Psychopharmacology, 2000, Volume: 148, Issue:1

    On the heels of clozapine, we now have a number of newer agents (risperidone, olanzapine, quetiapine, sertindole, and ziprasidone). Are they all the same? What are the differences? How do we best understand them? In this article we review current clinical evidence to compare these issues on four measures of atypicality: EPS, prolactin elevation, superior efficacy in refractory/positive symptoms and efficacy against negative symptoms. All the newer agents are superior on EPS and, with the exception of risperidone, avoid prolactin elevation. Clozapine shows the most convincing efficacy in refractory schizophrenia, although comparative data concerning risperidone's benefit in this respect are also emerging. It is unclear, however, whether any of the agents produce a greater effect than conventional antipsychotics against positive symptoms in responsive patients. Both clozapine and olanzapine have demonstrated superior efficacy against negative symptoms, although it remains controversial whether this is an effect on primary or secondary symptoms. The precise pharmacologic mechanisms underlying "atypicality" remain unclear, but several conceptual frameworks are highlighted that characterize, and perhaps differentiate, these newer agents.

    Topics: Antipsychotic Agents; Basal Ganglia Diseases; Clinical Trials as Topic; Clozapine; Humans; Prolactin; Schizophrenia; Terminology as Topic

2000
Extrapyramidal side effects, tardive dyskinesia, and the concept of atypicality.
    The Journal of clinical psychiatry, 2000, Volume: 61 Suppl 3

    The most frequent problems associated with the older generation of antipsychotic agents are extrapyramidal side effects (EPS) and tardive dyskinesia. Neuroleptic-induced EPS are thought to be caused by blockade of nigrostriatal dopamine tracts resulting in a relative increase in cholinergic activity; tardive dyskinesia is less well understood but is thought to be a supersensitivity response to chronic dopamine blockade. The leading hypothesis for the mechanism of action of the newer generation of atypical antipsychotics is the presence of a high serotonin-to-dopamine receptor blockade ratio in the brain. When serotonergic activity is blocked-as is the case with atypical antipsychotics-dopamine release increases and balances out the dopamine blockade effect at postsynaptic receptor sites, which results in few or no EPS. Prospective data indicate that the risk of tardive dyskinesia in patients taking atypical antipsychotics is less than that for those taking typical antipsychotics. This article reviews the mechanisms of neuroleptic-induced EPS and tardive dyskinesia and discusses the relationship between these movement disorders and atypical antipsychotic agents.

    Topics: Antipsychotic Agents; Basal Ganglia Diseases; Benzodiazepines; Brain; Clozapine; Dibenzothiazepines; Humans; Movement Disorders; Olanzapine; Pirenzepine; Quetiapine Fumarate; Receptors, Dopamine; Receptors, Serotonin; Risk Factors; Risperidone

2000
Will the novel antipsychotics significantly ameliorate neuropsychological deficits and improve adaptive functioning in schizophrenia?
    Psychological medicine, 1999, Volume: 29, Issue:1

    Topics: Antipsychotic Agents; Basal Ganglia Diseases; Clozapine; Cognition Disorders; Humans; Reaction Time; Risperidone; Schizophrenia; Schizophrenic Psychology; Severity of Illness Index

1999
Tardive dyskinesia and atypical antipsychotic drugs.
    Schizophrenia research, 1999, Mar-01, Volume: 35 Suppl

    Typical antipsychotic agents produce central nervous system effects, especially extrapyramidal symptoms (EPS) and tardive dyskinesia (TD). Nearly every patient who receives neuroleptic therapy has one or more identifiable risk factors for TD, among the most significant of which are older age, female gender, presence of EPS, diabetes mellitus, affective disorders, and certain parameters of neuroleptic exposure (i.e. dose and duration of therapy). The typical course of TD is a gradual onset after several years of drug therapy, followed by slow improvement or remission, but a large number of patients have persistent TD with irreversible symptoms. In the management of TD, the patient's mental status is of primary concern. Currently, no uniformly safe and effective therapies for TD exist, though a variety of therapeutic agents, including some of the atypical neuroleptics, have been reported to treat TD successfully in some patients. Because TD liability is so much lower with novel antipsychotic therapy, all patients who have TD or are at risk for TD, as well as EPS, should be considered candidates for switching to these new drugs.

    Topics: Adult; Age Factors; Aged; Antipsychotic Agents; Basal Ganglia Diseases; Benzodiazepines; Clozapine; Dyskinesia, Drug-Induced; Female; Humans; Male; Middle Aged; Olanzapine; Pirenzepine; Risperidone; Schizophrenia; Sex Factors

1999
Antipsychotics from theory to practice: integrating clinical and basic data.
    The Journal of clinical psychiatry, 1999, Volume: 60 Suppl 8

    The recent introduction of the atypical antipsychotics into the treatment arena for psychoses and related disorders comes with justifiable excitement. These newer antipsychotics offer several clinical benefits over the conventional antipsychotics, which have been the mainstays of care thus far. The primary advantage of these atypical agents is their superior side effect profiles, particularly with regard to extrapyramidal side effects (EPS). The implications from a reduction in EPS touch on virtually every aspect of pathology in schizophrenic illness, including short- and long-term movement disorders, negative symptoms, noncompliance, cognitive dysfunction, and dysphoria. It should be emphasized that while atypical antipsychotics share many clinical attributes, there are also substantial differences among them. This review will examine the pharmacology, clinical efficacy, and side effect profiles of the atypical antipsychotics and attempt to relate the attributes observed in clinical practice and clinical trials to their basic pharmacologic profiles. There is a fair, but not perfect, correspondence between the pharmacologic profiles of the different atypical antipsychotics and their respective clinical attributes. After a comparative overview of their receptor-binding profiles, a brief pharmacokinetic summary will be provided. Finally, the clinical profiles of these agents will be summarized with regard to both their efficacy and adverse effects.

    Topics: Animals; Antipsychotic Agents; Basal Ganglia Diseases; Benzodiazepines; Clinical Trials as Topic; Clozapine; Dose-Response Relationship, Drug; Humans; Limbic System; Models, Biological; Olanzapine; Pirenzepine; Psychotic Disorders; Receptors, Neurotransmitter; Risperidone; Schizophrenia

1999
The efficacy, safety, and tolerability of antipsychotics in the elderly.
    The Journal of clinical psychiatry, 1999, Volume: 60 Suppl 8

    Antipsychotic medications are among the most widely prescribed class of medications for elderly patients. Despite their high use, few studies document the efficacy, safety, and tolerability of these agents in this patient population. This is unfortunate because, as a group, the elderly are exceptionally sensitive to the adverse effects associated with antipsychotics, in particular, the extrapyramidal side effects (EPS). The atypical antipsychotics with their lower propensity to cause EPS and lower need for augmenting anticholinergic medication have introduced new options for elderly patients who need antipsychotic therapy for a number of psychiatric and neurologic disorders with psychotic manifestations. This review covers the pharmacologic, clinical, and regulatory issues involving antipsychotic use in elderly patients that warrant consideration by the practicing psychiatrist.

    Topics: Accidental Falls; Age Factors; Antipsychotic Agents; Basal Ganglia Diseases; Clinical Trials as Topic; Clozapine; Drug Costs; Drug Interactions; Dyskinesia, Drug-Induced; Humans; Hyperprolactinemia; Osteoporosis; Psychotic Disorders; Weight Gain

1999
Behavioural pharmacology of the new generation of antipsychotic agents.
    The British journal of psychiatry. Supplement, 1999, Issue:38

    In conclusion, the newer agents all have behavioural profiles which can be clearly differentiated from those of the older, classical agents. Behavioural data indicate that to a greater or lesser extent, all the newer antipsychotics will produce fewer acute EPS than the older agents. However, the new 'atypical' agents all have distinct profiles. Olanzapine has a profile similar to that of clozapine, albeit somewhat more potent. Olanzapine, like clozapine, displays a wide margin between the doses predictive of efficacy and those which induce EPS. The compound also substitutes for clozapine in drug discrimination assays and increases punished responding in a conflict paradigm. Quetiapine also has a clozapine-like profile, although it lacks the cholinergic receptor affinity and is relatively weak in most behavioural assays. Quetiapine, like olanzapine, also reverses PCP-induced deficits, and substitutes for clozapine in drug discrimination assays. However, no data are currently available regarding quetiapine's action in anxiolytic tests. Risperidone, sertindole and ziprasidone have profiles of activity different from those of older agents, predominantly due to their 5-HT2a affinity. All these agents possess some properties similar to those of clozapine, but there are some differences: for example, risperidone and sertindole fail to substitute for clozapine in drug discrimination assays and are inactive in classical conflict models of anxiety. It is more difficult to make an accurate assessment of the behavioural profile of ziprasidone, due to a lack of published data. Given the behavioural differences exhibited by animals receiving the new antipsychotic agents, one would predict that these drugs will have distinct clinical profiles. All the agents display activity indicative of agents with a reduced propensity to induce EPS. However, significant differences may be observed in their efficacy against negative and cognitive symptoms. It will be important to assess the clinical profiles of these agents carefully if the predictive value of the pre-clinical 'models' is to be improved.

    Topics: Animals; Antipsychotic Agents; Basal Ganglia Diseases; Behavior; Clozapine; Dopamine Antagonists; Humans; Rats; Schizophrenia; Serotonin Antagonists

1999
Suicide in schizophrenia: risk factors and clozapine treatment.
    The Journal of clinical psychiatry, 1998, Volume: 59 Suppl 3

    Suicide is the major cause of premature death in patients with schizophrenia. Among these patients, 40% report suicidal thoughts, 20% to 40% make unsuccessful suicide attempts, and 9% to 13% end their lives by suicide. Traditional antipsychotic drugs undertreat many schizophrenic patients and can produce serious side effects, such as tardive dyskinesia. Clozapine is the only antipsychotic drug that has been shown in controlled clinical trials to be effective in reducing both positive and negative symptoms in schizophrenic patients who fail to respond to typical neuroleptic drugs. The potential decrease in suicide among schizophrenic patients treated with clozapine is estimated to be as high as 85%. Treatment with clozapine is cost-effective, and the significant decrease in the risk of suicide far outweighs the very low risk of mortality from agranulocytosis. Clozapine should be considered for treatment of both neuroleptic-resistant and neuroleptic-responsive schizophrenic patients who have persistent suicidal thoughts or behavior.

    Topics: Adult; Aged; Agranulocytosis; Antipsychotic Agents; Basal Ganglia Diseases; Clozapine; Cost-Benefit Analysis; Dyskinesia, Drug-Induced; Female; Humans; Infant, Newborn; Male; Middle Aged; Risk Assessment; Risk Factors; Schizophrenia; Schizophrenic Psychology; Suicide; Suicide Prevention

1998
Effects of clozapine therapy in schizophrenic individuals at risk for tardive dyskinesia.
    The Journal of clinical psychiatry, 1998, Volume: 59 Suppl 3

    Neuroleptics were the first modern class of pharmacotherapeutic agents available for the treatment of schizophrenia. Although they were effective in reducing florid psychotic symptoms, up to 90% of treated individuals subsequently developed extrapyramidal symptoms (EPS) (akathisia, dystonia, or parkinsonism), and about 20% developed tardive dyskinesia (TD). When clozapine became commercially available for treatment-resistant and treatment-intolerant (i.e., prone to EPS and TD) schizophrenic individuals, it became apparent that an antipsychotic need not induce motor side effects to be efficacious in reducing the symptomatology of schizophrenia. Sociodemographic, behavioral, and clinical predictors of TD are useful in identifying a subset of schizophrenic individuals who would benefit from treatment with clozapine, the prototype atypical antipsychotic whose efficacy and motor side effect profile are superior to those of chlorpromazine. This favorable motor side effect profile of clozapine contributes to improved patient outcomes by reducing noncompliance, substance abuse, and suicide, resulting in improved quality of life and savings on health care costs.

    Topics: Age Factors; Aged; Basal Ganglia Diseases; Clozapine; Dyskinesia, Drug-Induced; Female; Humans; Male; Middle Aged; Prevalence; Risk Factors; Schizophrenia; Substance-Related Disorders; Suicide; Suicide Prevention; Treatment Outcome; Treatment Refusal

1998
Maximizing clozapine therapy: managing side effects.
    The Journal of clinical psychiatry, 1998, Volume: 59 Suppl 3

    Since its introduction to the United States in 1990, the benefits of clozapine use have been repeatedly validated. Clozapine remains the only antipsychotic with proven efficacy in treatment-resistant schizophrenia. Because clozapine has been part of the psychiatric pharmacopeia for considerably less time than neuroleptics, which have dominated the field for over 4 decades, its underutilization may be partly attributed to a lack of experience in managing associated side effects. Most side effects associated with clozapine are typical of antipsychotics in general, and with clozapine, these side effects are typically benign, tolerable, and manageable. It is conceivable that there remains a concern over the risk of agranulocytosis. However, the mandatory blood monitoring carried out through the Clozaril National Registry has considerably reduced the incidence of fully developed cases of agranulocytosis from premarketing values of approximately 1% to 2% to current values of 0.38% and virtually prevented mortalities. These values are likely to decrease further with the application of cytokine augmentation therapy among patients developing blood dyscrasias. Many side effects of clozapine are observed early after treatment onset and are greatly reduced by dose adjustments. Appropriate management of side effects will facilitate a maximization of the benefits of clozapine treatment. Clearly, the benefits of clozapine therapy far outweigh its risks.

    Topics: Agranulocytosis; Antipsychotic Agents; Basal Ganglia Diseases; Chemical and Drug Induced Liver Injury; Clozapine; Drug Administration Schedule; Drug Monitoring; Humans; Incidence; Risk Factors; Schizophrenia; Sleep Wake Disorders; Tachycardia; Urinary Incontinence; Weight Gain

1998
Adverse effects of the atypical antipsychotics. Collaborative Working Group on Clinical Trial Evaluations.
    The Journal of clinical psychiatry, 1998, Volume: 59 Suppl 12

    Adverse effects of antipsychotics often lead to noncompliance. Thus, clinicians should address patients' concerns about adverse effects and attempt to choose medications that will improve their patients' quality of life as well as overall health. The side effect profiles of the atypical antipsychotics are more advantageous than those of the conventional neuroleptics. Conventional agents are associated with unwanted central nervous system effects, including extrapyramidal symptoms (EPS), tardive dyskinesia, sedation, and possible impairment of some cognitive measures, as well as cardiac effects, orthostatic hypotension, hepatic changes, anticholinergic side effects, sexual dysfunction, and weight gain. The newer atypical agents have a lower risk of EPS, but are associated in varying degrees with sedation, cardiovascular effects, anticholinergic effects, weight gain, sexual dysfunction, hepatic effects, lowered seizure threshold (primarily clozapine), and agranulocytosis (clozapine only). Since the incidence and severity of specific adverse effects differ among the various atypicals, the clinician should carefully consider which side effects are most likely to lead to the individual's dissatisfaction and noncompliance before choosing an antipsychotic for a particular patient.

    Topics: Agranulocytosis; Antipsychotic Agents; Basal Ganglia Diseases; Benzodiazepines; Central Nervous System Diseases; Clozapine; Dibenzothiazepines; Drug Interactions; Dyskinesia, Drug-Induced; Health Status; Humans; Hypotension, Orthostatic; Olanzapine; Pirenzepine; Quality of Life; Quetiapine Fumarate; Receptors, Cholinergic; Risperidone; Schizophrenia; Sexual Dysfunctions, Psychological; Sleep Wake Disorders; Treatment Refusal; Weight Gain

1998
Assessment of EPS and tardive dyskinesia in clinical trials. Collaborative Working Group on Clinical Trial Evaluations.
    The Journal of clinical psychiatry, 1998, Volume: 59 Suppl 12

    The incidence of acute extrapyramidal symptoms (EPS)--akathisia, dystonia, and parkinsonism--associated with traditional antipsychotics varies, but most researchers agree that neuroleptic-induced EPS occur in 50% to 75% of patients who take conventional antipsychotics. Atypical antipsychotics were developed to widen the therapeutic index and to reduce EPS. Although the mechanisms are unclear, the risk of EPS is less with the novel antipsychotics than with conventional drugs, and agents that produce low levels of acute EPS are likely to produce less tardive dyskinesia. Nevertheless, clinicians should exercise caution when comparing data from investigations of the novel antipsychotics and, until long-term data become available, should administer the new drugs at doses below the EPS-producing level.

    Topics: Akathisia, Drug-Induced; Antipsychotic Agents; Basal Ganglia Diseases; Benzodiazepines; Clinical Trials as Topic; Clozapine; Dibenzothiazepines; Drug Administration Schedule; Dyskinesia, Drug-Induced; Dystonia; Humans; Olanzapine; Parkinson Disease, Secondary; Pirenzepine; Psychotic Disorders; Quetiapine Fumarate; Risperidone; Schizophrenia; Substance Withdrawal Syndrome

1998
Assessing the effects of atypical antipsychotics on negative symptoms. Collaborative Working Group on Clinical Trial Evaluations.
    The Journal of clinical psychiatry, 1998, Volume: 59 Suppl 12

    Attempts to clarify the domains of schizophrenia gained importance when the atypical antipsychotics joined the armamentarium of schizophrenia treatments because of evidence that these agents are superior to conventional antipsychotics for the treatment of negative symptoms. Negative symptoms can be divided into 3 components: (1) deficit or primary enduring negative symptoms that may or may not respond to treatment, (2) primary nonenduring negative symptoms, and (3) secondary negative symptoms that are associated with positive symptoms, extrapyramidal symptoms, depression, and environmental deprivation. The atypical antipsychotics have generally been found to be more effective than conventional antipsychotics against the totality of negative symptoms, but their effects on specific components are still under study. Sophisticated statistical tools such as path analysis have been used in investigations of the direct and indirect effects of atypical antipsychotics on negative symptoms, but these tools have limitations. Future study is needed to identify specific components of negative symptoms that may respond preferentially to one or another of the atypical antipsychotics.

    Topics: Antipsychotic Agents; Basal Ganglia Diseases; Clozapine; Delusions; Depressive Disorder; Hallucinations; Humans; Models, Statistical; Multivariate Analysis; Psychiatric Status Rating Scales; Regression Analysis; Risperidone; Schizophrenia; Schizophrenic Psychology

1998
The relationship of pharmacology to side effects.
    The Journal of clinical psychiatry, 1997, Volume: 58 Suppl 10

    Most traditional neuroleptics have a narrow therapeutic-to-toxic index, and thus, the novel antipsychotics are the result of a search to substantially widen the distance between the dose that treats psychosis and the one that produces adverse effects. In vitro binding profiles have been created for the atypical antipsychotics that have been approved by the U.S. Food and Drug Administration (FDA)-clozapine, olanzapine, and risperidone and those that are under FDA review-quetiapine and sertindole. These profiles, which were compared with that of the typical neuroleptic haloperidol, provide guidance for predicting the adverse effects produced by these drugs. Most conventional antipsychotics have central nervous system effects, particularly extrapyramidal symptoms (EPS) and tardive dyskinesia, sedation, and dulling of cognition. Other adverse effects of the typical antipsychotics include the neuroleptic malignant syndrome, orthostatic hypotension, changes in liver function, anticholinergic and antiadrenergic side effects, sexual dysfunction, and weight gain. The newer agents have a lower incidence of EPS and tardive dyskinesia, while weight gain and changes in blood pressure and liver function tests are adverse effects that have been associated with the use of the newer agents. The favorable side effect profile of these new antipsychotics is likely to make patients more willing to continue treatment, and thus these agents represent a step forward in the treatment of patients with severe, chronic mental illness.

    Topics: Akathisia, Drug-Induced; Antipsychotic Agents; Basal Ganglia Diseases; Benzodiazepines; Clozapine; Dose-Response Relationship, Drug; Dyskinesia, Drug-Induced; Haloperidol; Humans; Olanzapine; Parkinson Disease, Secondary; Pirenzepine; Receptors, Neurotransmitter; Seizures; Sleep; Weight Gain

1997
Extrapyramidal symptoms during long-term treatment with antipsychotics: special focus on clozapine and D1 and D2 dopamine antagonists.
    Neuropsychopharmacology : official publication of the American College of Neuropsychopharmacology, 1996, Volume: 14, Issue:3 Suppl

    In schizophrenic patients in maintenance treatment, clozapine, compared to classic neuroleptics, induces relatively few extrapyramidal syndromes (EPS), especially less akathisia and tremor and usually no dystonia or rigidity. In patients with dyskinetic movements (acute or tardive) induced by other neuroleptics, clozapine may reduce or even remove dyskinesia or permit it to disappear. It cannot, however, be excluded that clozapine can induce dyskinesia in extremely rare cases, but it seems more likely that this is due to previous treatment with classic neuroleptics. The earlier clozapine is started, the less chance of development of dyskinesia. The low level of EPS with clozapine may be linked to the special receptor-binding profile of this drug: during treatment with therapeutic doses of clozapine, the level of D2 receptor blockade is too low (40% to 50% occupancy by positron emission tomography) to induce EPS, and the D1 receptor blockade (also 40% to 50% occupancy) has a lower EPS potential than D2 blockade. This binding profile may at the same time contribute to the special antipsychotic properties of clozapine. Other receptor affinities may contribute to the beneficial effect of clozapine in EPS and schizophrenia.

    Topics: Antipsychotic Agents; Basal Ganglia Diseases; Clozapine; Dopamine Antagonists; Humans; Movement Disorders

1996
5-HT2 antagonism and EPS benefits: is there a causal connection?
    Psychopharmacology, 1996, Volume: 124, Issue:1-2

    This article examines the hypothesis that 5-HT2 antagonism ameliorates extrapyramidal side effects (EPS) induced by the blockade of D2 dopamine receptors by antipsychotics. Neuroanatomical and neurophysiological data confirm the existence of pathways whereby 5-HT2 antagonism may influence EPS. The experimental data in rodents is marginally positive, but shows that the net effect of 5-HT2 antagonism is dependent upon the precise conditions under which catalepsy is induced. The data in monkeys are mainly negative. Studies in patients who have received adjunct 5-HT2 antagonists in addition to typical neuroleptics lend some support the the hypothesis, but are not conclusive. It is reasoned that 5-HT2 antagonism plays no role in clozapine's freedom from EPS, but it may be responsible for risperidone's decreased propensity to cause EPS. The article concludes that there is support for a conditional role of 5-HT2 in decreasing EPS: 5-HT2 antagonists may delay the onset and decrease the severity of EPS but cannot totally eliminate its occurrence. The implications of these findings for the next generation of combined 5-HT2/D2 antagonists are discussed.

    Topics: Animals; Antipsychotic Agents; Basal Ganglia Diseases; Clozapine; Humans; Receptors, Dopamine D2; Risperidone; Serotonin Antagonists

1996
Mechanisms of action of atypical antipsychotic drugs: a critical analysis.
    Psychopharmacology, 1996, Volume: 124, Issue:1-2

    Various criteria used to define atypical antipsychotic drugs include: 1) decrease, or absence, of the capacity to cause acute extrapyramidal motor side effects (acute EPSE) and tardive dyskinesia (TD); 2) increased therapeutic efficacy reflected by improvement in positive, negative, or cognitive symptoms; 3) and a decrease, or absence, of the capacity to increase prolactin levels. The pharmacologic basis of atypical antipsychotic drug activity has been the target of intensive study since the significance of clozapine was first appreciated. Three notions have been utilized conceptually to explain the distinction between atypical versus typical antipsychotic drugs: 1) dose-response separation between particular pharmacologic functions; 2) anatomic specificity of particular pharmacologic activities; 3) neurotransmitter receptor interactions and pharmacodynamics. These conceptual bases are not mutually exclusive, and the demonstration of limbic versus extrapyramidal motor functional selectivity is apparent within each arbitrary theoretical base. This review discusses salient distinctions predominantly between prototypic atypical and typical antipsychotic drugs such as clozapine and haloperidol, respectively. In addition, areas of common function between atypical and typical antipsychotic drug action may also be crucial to our identification of pathophysiological foci of the different dimensions of schizophrenia, including positive symptoms, negative symptoms, and neurocognitive deficits.

    Topics: Animals; Antipsychotic Agents; Basal Ganglia Diseases; Behavior, Animal; Biogenic Amines; Brain; Clozapine; Dopamine; Dose-Response Relationship, Drug; Haloperidol; Humans; Receptors, Dopamine; Schizophrenia

1996
Side effect profiles of new antipsychotic agents.
    The Journal of clinical psychiatry, 1996, Volume: 57 Suppl 11

    Although neuroleptic drugs have become the mainstay of treating acute and chronic psychosis, they are substantially limited by troublesome side effects. The traditional neuroleptic drugs have a wide array of central nervous system and peripheral system side effects that often lead to problems in management or patient noncompliance. Of particular difficulty are the extrapyramidal symptoms and tardive dyskinesia. However, other side effects of seizures, sedation, neuroleptic malignant syndrome and cardiovascular, hematologic, endocrinological, and weight gain problems remain as clinical management challenges posed by existing antipsychotic drug therapy. Considerable progress has been made in improving the motor side effect profile with the advent of clozapine and risperidone. However, each of these drugs has its own dose-limiting side effect profile. Two new drugs, olanzapine and sertindole, are now added to the pharmacopeia for treating psychosis. They further improve the benefit/ risk ratio because they have even fewer EPS and other side effects. Overall, these new antipsychotic agents greatly improve the treatment of psychosis by reducing drug-induced morbidity and improving the quality of life for patients.

    Topics: Antipsychotic Agents; Basal Ganglia Diseases; Benzodiazepines; Clozapine; Dyskinesia, Drug-Induced; Humans; Imidazoles; Indoles; Neuroleptic Malignant Syndrome; Olanzapine; Pirenzepine; Psychotic Disorders; Risperidone; Schizophrenia; Seizures; Sleep; Weight Gain

1996
Serotonin, schizophrenia and antipsychotic drug action.
    Schizophrenia research, 1995, Volume: 14, Issue:3

    A rapidly growing body of data suggests that dysfunction in serotonergic (5-HT) function may be involved in the pathophysiology of schizophrenia, and that pharmacologic agents for this illness have their therapeutic effects mediated through serotonergic mechanisms. The purpose of this paper is to critically review data relevant to 5-HT's role in the pathophysiology and drug treatment of schizophrenia. Pathophysiologic evidence includes the psychotomimetic effects of lysergic acid (LSD), postmortem studies, single-dose 'challenge' studies and investigations of CSF and peripheral levels of 5-HT and its metabolites. The current nomenclature, potential therapeutic effects and importance of 5-HT receptor subtype antagonism will be examined. In addition, relatively novel strategies of 5-HT uptake blockade and direct acting 5-HT agonists will be assessed. A hypothesis of cortical-subcortical imbalance with an increase in subcortical 5-HT function responsible for positive symptoms and a decrease in prefrontal 5-HT function responsible for negative symptoms is proposed. Future implications of these data are discussed.

    Topics: Antipsychotic Agents; Basal Ganglia Diseases; Clozapine; Humans; Isoxazoles; Piperazines; Piperidines; Risperidone; Schizophrenia; Serotonin; Tryptophan

1995
Prospects for pharmacotherapy of schizophrenia.
    Lancet (London, England), 1995, Mar-04, Volume: 345, Issue:8949

    Topics: Antipsychotic Agents; Basal Ganglia Diseases; Clozapine; Humans; Isoxazoles; Piperidines; Receptors, Dopamine; Receptors, Dopamine D2; Receptors, Serotonin; Risperidone; Schizophrenia

1995
Adverse effects of antipsychotic drugs.
    Drug safety, 1993, Volume: 9, Issue:6

    Since the introduction of chlorpromazine in the 1950s, neuroleptic medications have been the mainstay of treatment of schizophrenia and other psychotic disorders. These medications do not always lead to complete remission of symptoms but they have allowed many patients to lead more productive and satisfying lives away from the restrictions of chronic hospitalisation. However, neuroleptics are associated with a number of adverse effects that can compromise their effectiveness. Extrapyramidal adverse effects include acute dystonic reactions, neuroleptic-induced Parkinsonism and akathisia. They can often be treated with neuroleptic dose reduction, addition of anticholinergic or beta-blocking agents, or medication change. Later-onset movement disorders such as tardive dyskinesia or dystonia require careful evaluation and may be treated with dose reduction or change of neuroleptic to an atypical agent. Potentially fatal reactions such as agranulocytosis and neuroleptic malignant syndrome can rarely occur and often require significant medical intervention. Clozapine offers some advantages over 'typical' neuroleptics but has a unique adverse effect profile which includes agranulocytosis.

    Topics: Akathisia, Drug-Induced; Antipsychotic Agents; Basal Ganglia Diseases; Clozapine; Dyskinesia, Drug-Induced; Dystonia; Humans; Neuroleptic Malignant Syndrome; Parasympathetic Nervous System; Parkinson Disease, Secondary

1993
Dopamine receptors in the basal ganglia: relevance to Parkinson's disease.
    Movement disorders : official journal of the Movement Disorder Society, 1993, Volume: 8, Issue:3

    At least five receptors for dopamine (D1-D5) have been recognised from molecular biological studies, and their pharmacological properties and brain localisations have been determined. The D1 and D2 subtypes are the principal subtypes in brain, and their cellular localisations in the caudate nucleus and putamen have been determined. With recent advances in the understanding of basal ganglia neuronal function, these localisation data enable insights into the mode of action of drugs used at present and in the future to treat Parkinson's disease.

    Topics: Basal Ganglia; Basal Ganglia Diseases; Brain; Clozapine; Dopamine Agents; Dopamine D2 Receptor Antagonists; Female; Haloperidol; Humans; Levodopa; Male; Neostriatum; Neural Pathways; Parkinson Disease; Receptors, Dopamine D1; Receptors, Dopamine D2; Sulpiride

1993
[Effect of clozapine in schizophrenia; starting points for current pharmacotherapeutics].
    Nederlands tijdschrift voor geneeskunde, 1993, Jul-17, Volume: 137, Issue:29

    Topics: Basal Ganglia Diseases; Clozapine; Humans; Receptors, Serotonin; Schizophrenia; Serotonin Antagonists

1993
Clozapine and D1/D2 antagonism in extrapyramidal functions.
    The British journal of psychiatry. Supplement, 1992, Issue:17

    One of the main advantages of clozapine is that it rarely produces extrapyramidal syndromes and tardive dyskinesia. This advantage is linked to the atypical biochemical profile of clozapine, especially its combined and low blockade of D1 and D2 receptors. The level of D2 receptor blockade is too low to induce extrapyramidal side-effects, and D1 antagonists have a lower extrapyramidal side-effect potential than traditional D2 neuroleptics, especially with respect to dystonia. The combined and balanced D1/D2 receptor blockade may prevent the development of a dysbalance between D1/D2 receptor function (in favour of D1) which otherwise might lead to tardive dyskinesia.

    Topics: Animals; Basal Ganglia Diseases; Clozapine; Dyskinesia, Drug-Induced; Female; Haplorhini; Humans; Male; Receptors, Dopamine

1992
Clinical efficacy of clozapine in treatment-refractory schizophrenia: an overview.
    The British journal of psychiatry. Supplement, 1992, Issue:17

    The treatment of patients with schizophrenia who fail to respond to antipsychotic medications remains a challenge. Despite numerous attempts to establish effective somatic treatment approaches for this population, clozapine appears to be the only well established alternative. Depending upon trial duration and response criteria, between 30% and 60% of previously unresponsive patients appear to derive clinically significant benefit from clozapine. Clozapine also has important advantages in terms of its reduced propensity to produce extrapyramidal side-effects. Agranulocytosis remains an important risk, so strategies to improve the benefit-to-risk ratio should be explored. Issues such as trial duration, dosage, blood levels and predictors of response require additional study.

    Topics: Agranulocytosis; Basal Ganglia Diseases; Clozapine; Female; Humans; Male; Schizophrenia; Schizophrenic Psychology

1992
Update on the clinical efficacy and side effects of clozapine.
    Schizophrenia bulletin, 1991, Volume: 17, Issue:2

    Clozapine (CLOZ) is an atypical antipsychotic drug being used with increasing frequency throughout the world and has recently been commercially marketed in the United States. Its unique properties make it a promising but challenging drug to use in the treatment of schizophrenia. In order to use CLOZ most effectively and efficiently, clinicians must be aware of its potential benefits and risks. This report is a review and critical evaluation of current knowledge regarding the clinical efficacy and side effects of CLOZ. Although CLOZ has proven to be effective in some treatment-refractory schizophrenic patients and to produce relatively few extrapyramidal side effects compared to classical neuroleptic drugs, several issues require further investigation including what defines neuroleptic intolerance, the optimal dose range, and the appropriate duration of a CLOZ treatment trial. Similarly, studies are needed to determine what role CLOZ should have in the treatment of patients with predominantly negative symptoms and those patients who are only partially responsive to standard neuroleptics. In addition, important questions remain as to what other conditions might be indications for CLOZ, for example, schizoaffective disorder, affective psychoses, and idiopathic Parkinson's disease.

    Topics: Agranulocytosis; Basal Ganglia Diseases; Clozapine; Humans; Nervous System; Schizophrenia

1991
Clozapine: neuroleptic-induced EPS and tardive dyskinesia.
    Psychopharmacology, 1989, Volume: 99 Suppl

    Clozapine has had a uniquely favorable motor system side effect profile since its initial evaluations. This has been convincingly corroborated by many double blind, single blind, and open studies treating acute and chronic psychosis. The acute extrapyramidal syndromes of dystonia, akathisia and parkinsonism infrequently occur, whereas these syndromes develop in up to 75% of patients receiving traditional neuroleptics. Tardive dyskinesia can be suppressed with higher doses of clozapine given over extended periods. However, an antipsychotic effect can be achieved in many patients at doses below the dyskinesia suppressing level. There is no established causative relationship between clozapine and tardive dyskinesia, but there is a theoretical basis that this may occur. Preliminary data suggest clozapine has mild antiparkinsonian effects as well as efficacy in controlling dopamine agonist-induced psychosis without aggravating parkinsonism. A much wider use of clozapine will further characterize the magnitude of differences compared to other neuroleptics, and identify additional indications for this special compound.

    Topics: Basal Ganglia Diseases; Clozapine; Dibenzazepines; Dyskinesia, Drug-Induced; Humans

1989
Significance of neurochemical parameters in the preclinical evaluation of neuroleptic drugs.
    Pharmacology & therapeutics. Part B: General & systematic pharmacology, 1979, Volume: 5, Issue:1-3

    Topics: Animals; Antipsychotic Agents; Basal Ganglia Diseases; Brain Chemistry; Clozapine; Corpus Striatum; Dopamine; Drug Evaluation, Preclinical; gamma-Aminobutyric Acid; Haloperidol; Neural Pathways; Neurons; Parasympathetic Nervous System; Postmortem Changes; Substantia Nigra; Tyramine

1979

Trials

23 trial(s) available for clozapine and Basal-Ganglia-Diseases

ArticleYear
The effects of eicosapentaenoic acid in tardive dyskinesia: a randomized, placebo-controlled trial.
    Schizophrenia research, 2006, Volume: 84, Issue:1

    Worldwide, conventional antipsychotic medication continues to be used extensively, and tardive dyskinesia (TD) remains a serious complication. The primary objective of the present study was to compare the efficacy of EPA versus placebo in reducing symptoms of TD.. This was a 12-week, double-blinded, randomized study of ethyl-EPA 2g/day versus placebo as supplemental medication, in patients with schizophrenia or schizoaffective disorder, with established TD.. Eighty-four subjects were randomized, of whom 77 were included in the analysis. Both the EPA and placebo groups displayed significant baseline to endpoint improvements in Extrapyramidal Symptom Rating Scale dyskinesia scores, but there were no significant between-group differences (p=0.4). Response rates (>or=30% improvement in TD symptoms) also did not differ significantly between EPA-treated subjects (45%) and placebo-treated subjects (32%) (p=0.6). However, a post-hoc linear mixed model repeated measures analysis of variance indicated an effect for treatment group and duration of TD. The EPA-treated patients had significantly greater mean reductions in dyskinesia scores initially, although this was not sustained beyond 6 weeks.. This trial failed to demonstrate an anti-dyskinetic effect for ethyl-EPA 2g/day on the primary efficacy measure. However, a modest and transient benefit is suggested in patients with more recent onset of TD. The lack of clear-cut efficacy could be explained on the basis of the dose of EPA being too low, the study being underpowered, TD being too chronic in the majority of cases, differences in dietary fatty acid intake, or that EPA lacks an anti-dyskinetic action.

    Topics: Adolescent; Adult; Antipsychotic Agents; Basal Ganglia Diseases; Clozapine; Double-Blind Method; Dyskinesia, Drug-Induced; Eicosapentaenoic Acid; Female; Humans; Male; Middle Aged; Psychotic Disorders; Schizophrenia

2006
A double-blind controlled study of adjunctive treatment with risperidone in schizophrenic patients partially responsive to clozapine: efficacy and safety.
    The Journal of clinical psychiatry, 2005, Volume: 66, Issue:1

    Several open trials and case studies have reported beneficial effects following the addition of risperidone for partial responders to clozapine. The purpose of this study was to carry out a placebo-controlled, randomized, double-blind trial of the efficacy, safety, and tolerability of adjunctive treatment with risperidone in patients with schizophrenia partially responsive to clozapine.. In this 6-week double-blind study, 30 patients with DSM-IV schizophrenia who had partial response to clozapine despite being treated for a mean of 32 months were randomly assigned to risperidone (N = 16) up to 6 mg/day or placebo (N = 14). Efficacy assessments included the Positive and Negative Syndrome Scale (PANSS), the Calgary Depression Scale, the Clinical Global Impressions-Severity of Illness scale, the Global Assessment of Functioning scale, and the Quality of Life Scale. A variety of safety and tolerability measures were also obtained. Data were collected between November 2001 and July 2003.. Significant improvement was noted in both groups on a variety of measures of psychopathology, but there was significantly greater improvement in the placebo-treated patients on the primary outcome measure, the PANSS positive symptom subscale. There were no significant differences between the treatment groups regarding extrapyramidal symptoms, weight gain, vital signs, serum clozapine levels, and QTc interval. The only side effect significantly more severe in risperidone-treated compared to placebo-treated patients was sedation. The patients treated with risperidone developed significant increases in plasma prolactin levels.. Adjunctive risperidone treatment in schizophrenia patients partially responsive to clozapine does not significantly improve psychopathology or quality of life compared to placebo in a 6-week period.

    Topics: Antipsychotic Agents; Basal Ganglia Diseases; Clozapine; Double-Blind Method; Drug Administration Schedule; Drug Therapy, Combination; Humans; Placebos; Prolactin; Prospective Studies; Psychiatric Status Rating Scales; Quality of Life; Risperidone; Schizophrenia; Schizophrenic Psychology; Treatment Outcome

2005
Olanzapine versus clozapine in treatment-resistant or treatment-intolerant schizophrenia.
    Progress in neuro-psychopharmacology & biological psychiatry, 2004, Volume: 28, Issue:1

    Clozapine has been the gold standard for treatment of patients with refractory schizophrenia but is associated with serious safety liabilities. This has prompted the search for therapeutic alternatives for treatment-resistant schizophrenia. The objective of this study was to compare the efficacy and safety of olanzapine versus clozapine in schizophrenic patients who failed to respond adequately to antipsychotic medication or who experienced intolerable adverse effects associated with the medication. This 18-week, randomized, double-blind, parallel study compared treatment with either olanzapine (5-25 mg/day, n=75) or clozapine (100-500 mg/day, n=72) in patients with schizophrenia who were nonresponsive to, or intolerant of, standard acceptable antipsychotic therapy. At the 18-week endpoint, no statistically significant differences were found between olanzapine and clozapine in any efficacy measure used: Positive and Negative Syndrome Scale (PANSS) total, positive, negative, or general psychopathology or Clinical Global Impression severity (CGI-S). Response rates based on the criteria of Kane et al. [Arch. Gen. Psychiatry 45 (1988) 789] were also not significantly different between olanzapine-treated (57.9%) and clozapine-treated patients (60.8%). There were no significant differences in measurements of extrapyramidal symptoms or electrocardiography, and no clinically and statistically significant changes were seen in vital signs or laboratory measures in either group. Both treatments were well tolerated. Olanzapine demonstrated similar efficacy to clozapine in patients who had failed previous treatment because of lack of efficacy (treatment resistance) or intolerable side effects (treatment intolerance). Olanzapine therefore presents a safe alternative in the treatment of refractory schizophrenia.

    Topics: Adolescent; Adult; Aged; Antipsychotic Agents; Basal Ganglia Diseases; Benzodiazepines; Body Weight; Clozapine; Double-Blind Method; Drug Resistance; Female; Humans; Male; Middle Aged; Olanzapine; Pirenzepine; Psychiatric Status Rating Scales; Schizophrenia

2004
Effectiveness of clozapine in neuroleptic-resistant schizophrenia: clinical response and plasma concentrations.
    Journal of psychiatry & neuroscience : JPN, 2002, Volume: 27, Issue:1

    To assess the relation between plasma concentrations of clozapine and its 2 main metabolites desmethyl clozapine and clozapine N-oxide, and clinical change in a sample of inpatients with schizophrenia who were resistant to conventional neuroleptics.. Thirty-seven patients (27 men and 10 women, mean age 34.8 yr) with treatment-resistant schizophrenia were treated with clozapine for 18 weeks; dosage was adjusted according to clinical response, and plasma concentrations of clozapine and of its metabolites were measured weekly by high-performance liquid chromatography. Clinical status was also assessed weekly with the Positive and Negative Syndrome Scale (PANSS). Patients were considered "responsive" if they showed at least a 20% improvement over their baseline PANSS ratings.. The mean endpoint clozapine dosage was 486.5 mg/day. There was a significant correlation between the daily dosage of clozapine and the plasma levels of clozapine and of its metabolites (p < 0.05). There was no correlation between the clozapine plasma level and the percent improvement on the PANSS. Clozapine plasma levels were not significantly different between those who responded to clozapine (n = 19) and those who did not (n = 18) and were not significantly different between patients who smoked (n = 28) and those who did not (n = 9). Receiver operating characteristic (ROC) curve analysis determined the plasma level threshold (above which a better clinical response was obtained) to be 550 ng/mL. Using the total of plasma levels of clozapine and its metabolites did not lead to a better sensitivity and specificity.. Our calculated plasma clozapine threshold was higher than that reported by others, but this may be related to the severity of symptoms of our patient sample. Monitoring plasma rates remains a useful tool, together with clinical evaluation, to establish the clozapine dosage for an optimum benefit-risk ratio.

    Topics: Adult; Antipsychotic Agents; Basal Ganglia Diseases; Clozapine; Drug Resistance; Female; Humans; Male; ROC Curve; Schizophrenia; Treatment Outcome

2002
Clinical predictors of response to clozapine treatment in ambulatory patients with schizophrenia.
    The Journal of clinical psychiatry, 2002, Volume: 63, Issue:5

    Despite the advent of new atypical antipsychotics, clozapine remains an important option in the treatment of patients with poor response to conventional antipsychotics. Clinicians would be well served if clinical characteristics could be identified that predict a favorable response to clozapine. A few studies addressing this issue have reported inconsistent results.. The association of clinical characteristics with a sustained response was investigated in 37 partially treatment-refractory outpatients with a DSM-III-R diagnosis of chronic schizophrenia who had been assigned to clozapine treatment in a double-blind, haloperidol-controlled, long-term (29-week) study of clozapine. Response was defined as a 20% decrease of the Brief Psychiatric Rating Scale (BPRS) psychosis factor score sustained over 2 consecutive ratings. Differences between responders and nonresponders with regard to selected baseline variables were analyzed with t tests and chi2 tests. In addition, Cox regression analyses were performed to identify variables that best predicted a response to clozapine treatment.. Clozapine responders were rated as less severely ill, showed a lesser degree of negative symptoms, and demonstrated fewer extrapyramidal side effects at baseline as compared with nonresponders. In addition, higher BPRS total scores--after controlling for the effects of the other variables--were associated with a response.. In a cohort of partially treatment-refractory outpatients, a favorable response to clozapine was associated with characteristics describing less severely ill patients. The history of patients did not affect their response to clozapine.

    Topics: Adult; Ambulatory Care; Antipsychotic Agents; Basal Ganglia Diseases; Brief Psychiatric Rating Scale; Chronic Disease; Clozapine; Double-Blind Method; Female; Haloperidol; Humans; Male; Probability; Psychiatric Status Rating Scales; Schizophrenia; Treatment Outcome

2002
A double-blind comparative study of clozapine and risperidone in the management of severe chronic schizophrenia.
    The American journal of psychiatry, 2001, Volume: 158, Issue:8

    This prospective, double-blind, multicenter, parallel-group study compared the efficacy and safety of therapeutic doses of clozapine and risperidone in patients with severe chronic schizophrenia and poor previous treatment response.. Male or female patients aged 18-65 years who met DSM-IV criteria for schizophrenia and study requirements for poor previous treatment response (N=273) were randomly assigned to double-blind treatment with either clozapine or risperidone administered over 12 weeks in increasing increments. The primary efficacy measures were the magnitude of improvement in Brief Psychiatric Rating Scale (BPRS) and Clinical Global Impression (CGI) scores. Adverse events were recorded throughout the study.. The magnitude of improvement in mean BPRS and CGI scores from baseline to end of the study was significantly greater in the clozapine group than in the risperidone group. Statistically significant differences in favor of clozapine were also seen for most of the secondary efficacy measures (Positive and Negative Syndrome Scale, Calgary Depression Scale, Psychotic Depression Scale, and Psychotic Anxiety Scale). The adverse event profile was similar for both treatment groups, with a lower risk of extrapyramidal symptoms in the clozapine group.. Clozapine showed superior efficacy over risperidone in this patient population. Both treatments were equally well tolerated as demonstrated through their adverse event profiles, although as expected clozapine was associated with a lower risk of extrapyramidal symptoms than risperidone.

    Topics: Adolescent; Adult; Aged; Antipsychotic Agents; Basal Ganglia Diseases; Chronic Disease; Clozapine; Double-Blind Method; Female; Humans; Male; Middle Aged; Psychiatric Status Rating Scales; Risk Factors; Risperidone; Schizophrenia; Schizophrenic Psychology; Severity of Illness Index; Treatment Outcome

2001
Clozapine and negative symptoms. An open study.
    Progress in neuro-psychopharmacology & biological psychiatry, 2000, Volume: 24, Issue:3

    1. Clozapine, the first atypical antipsychotic, has demonstrated an efficacy in the treatment of resistant schizophrenia. But one of the major challenge in the treatment of schizophrenia remains the lack of efficacy of antipsychotics on negative symptoms of schizophrenia. 2. The authors studied the efficacy of clozapine in an open study in a population of 51 patients, who met the DSM IV criteria for schizophrenia. Using the positive and negative symptom scale (P.A.N.S.S.), and the Extra Pyramidal Symptoms Rating Scale (E.S.R.S.), we try to identify the specificity of the action of clozapine on the different symptomatic dimensions of schizophrenia. 3. The efficacy of clozapine was clinically significant on the negative symptomatology but was delayed compared to the efficacy on the other dimensions of symptomatology evaluated using the PANSS. 4. Nine patients, were considered as deficit patients; in this sample clozapine also demonstrated a significant efficacy on negative symptoms. The efficacy of clozapine did not seem to be a consequence of the better neurological tolerance of this antipsychotic evaluated with ESRS.

    Topics: Adult; Antipsychotic Agents; Basal Ganglia Diseases; Clozapine; Female; Humans; Male; Schizophrenia; Severity of Illness Index; Treatment Outcome

2000
A naturalistic comparison of clozapine, risperidone, and olanzapine in the treatment of bipolar disorder.
    The Journal of clinical psychiatry, 2000, Volume: 61, Issue:9

    Our purpose was to evaluate the overall efficacy and tolerability of novel antipsychotic medications for patients with bipolar disorder type I.. A retrospective study of the Massachusetts General Hospital Bipolar Clinic database was carried out to identify 50 consecutive treatment trials in patients with DSM-IV bipolar disorder type I who had received adjunctive treatment with risperidone, olanzapine, or clozapine, along with standard mood stabilizers. The treatment charts of those patients (N = 42) were reviewed for details of adverse effects, tolerability, and efficacy of medication.. Overall results indicated equivalent efficacy in novel antipsychotic treatments according to change in Clinical Global Impressions scale score. Levels of extrapyramidal symptoms were similar in all groups and occurred in 12/42 patients (28.6%). Prolactin-related side effects were not observed in any patients. There were no cases of affective switch or worsening of mania. Substantial weight gain of more than 10 lb (4.5 kg) was significantly greater in patients treated with olanzapine.. These results suggest that the efficacy and tolerability of risperidone, olanzapine, and clozapine are similar in patients with bipolar disorder. One major differentiation factor of these drugs appears to be weight gain, particularly between olanzapine and risperidone. This may, in part, also be related to the need to use mood-stabilizing agents, like lithium or divalproex sodium, which may potentiate the weight-gain effect of novel antipsychotics.

    Topics: Adult; Antipsychotic Agents; Basal Ganglia Diseases; Benzodiazepines; Bipolar Disorder; Body Weight; Clozapine; Drug Administration Schedule; Drug Therapy, Combination; Female; Humans; Lithium; Male; Olanzapine; Pirenzepine; Psychiatric Status Rating Scales; Retrospective Studies; Risperidone; Treatment Outcome; Valproic Acid

2000
Clozapine and risperidone in chronic schizophrenia: effects on symptoms, parkinsonian side effects, and neuroendocrine response.
    The American journal of psychiatry, 1999, Volume: 156, Issue:2

    Clozapine and risperidone were the first two "second-generation" antipsychotic drugs approved for schizophrenia. There is currently little information about their comparative efficacy from head-to-head clinical trials. The purpose of this study was to examine the comparative efficacy of clozapine and risperidone for positive and negative symptoms, depression, parkinsonian side effects, and indexes of neuroendocrine function in schizophrenic patients who met a priori criteria for partial response to traditional neuroleptic agents.. After a baseline fluphenazine treatment period, 29 patients participated in a 6-week, double-blind, parallel-group comparison of the effects of these agents.. Clozapine was superior to risperidone for positive symptoms and parkinsonian side effects, but there were no significant differences between the drugs on two measures of negative symptoms, Brief Psychiatric Rating Scale total scores, and depression scores. The clozapine patients, but not the risperidone patients, demonstrated significant reductions from the fluphenazine baseline in positive symptoms, total symptoms, and depression. In addition, clozapine produced fewer effects on plasma prolactin than risperidone or fluphenazine. The mean daily doses during week 6 of the trial were 403.6 mg of clozapine and 5.9 mg of risperidone.. The findings from this study indicate that these drugs have both important differences and similarities in their comparative efficacy in chronically ill, partially responsive patients with schizophrenia. Further research on second-generation antipsychotic drugs in this patient population that addresses key methodological issues, such as optimal dose and treatment duration, are needed.

    Topics: Adult; Antipsychotic Agents; Basal Ganglia Diseases; Chronic Disease; Clozapine; Double-Blind Method; Drug Administration Schedule; Female; Human Growth Hormone; Humans; Hydrocortisone; Male; Parkinson Disease, Secondary; Prolactin; Psychiatric Status Rating Scales; Risperidone; Schizophrenia; Schizophrenic Psychology; Treatment Outcome

1999
The prevalence of acute extrapyramidal signs and symptoms in patients treated with clozapine, risperidone, and conventional antipsychotics.
    The Journal of clinical psychiatry, 1998, Volume: 59, Issue:2

    Acute extrapyramidal side effects (EPS) are a common phenomenon of treatment with conventional antipsychotics. Previous studies found that clozapine has little propensity to cause EPS, while risperidone produces some EPS, but at levels lower than those of conventional antipsychotics.. We compared the prevalence and severity of EPS in patients treated with clozapine, risperidone, or conventional antipsychotics for at least 3 months. Our main hypothesis was that there would be differences between the three treatment groups with regard to akathisia, measured with the Barnes Akathisia Scale, and extrapyramidal motor side effects (rigidity, rigidity factor, tremor, salivation), measured with the Simpson-Angus scale. Secondarily, we were interested in possible differences between the three groups with respect to the anticholinergic comedication and the subjective impression of the patients, measured with the van Putten scale.. We studied 106 patients (41 patients treated with clozapine, 23 patients with risperidone, and 42 patients treated with conventional antipsychotics). The sample was 57.5% male and had a mean +/- SD age of 36.6 +/- 9.3 years. The mean dose of antipsychotics calculated in chlorpromazine equivalents was 425.6 +/- 197.1 mg/day in the clozapine group, 4.7 +/- 2.1 mg/day in the risperidone group, and 476.5 +/- 476.9 mg/day in the group treated with conventional antipsychotics. The point-prevalence of akathisia was 7.3% in the clozapine group, 13% in the risperidone group, and 23.8% in the group treated with conventional antipsychotics. The point-prevalence of rigidity and cogwheeling respectively was 4.9% and 2.4% in the clozapine group, 17.4% and 17.4% in the risperidone group, and 35.7% and 26.2% in the group treated with conventional antipsychotics.. Our results indicate that risperidone is superior to conventional neuroleptics in that it causes fewer EPS. In comparison to clozapine, risperidone produces EPS levels that are intermediate between clozapine and conventional antipsychotic drugs.

    Topics: Acute Disease; Adolescent; Adult; Akathisia, Drug-Induced; Ambulatory Care; Antipsychotic Agents; Basal Ganglia Diseases; Clozapine; Dose-Response Relationship, Drug; Drug Administration Schedule; Female; Humans; Male; Middle Aged; Prevalence; Product Surveillance, Postmarketing; Psychotic Disorders; Risperidone; Schizophrenia; Severity of Illness Index

1998
Clinical and neurocognitive effects of clozapine and risperidone in treatment-refractory schizophrenic patients: a prospective study.
    The Journal of clinical psychiatry, 1998, Volume: 59, Issue:10

    Few controlled studies have compared the efficacy of clozapine and risperidone in treatment-refractory schizophrenic patients. The present study investigates the efficacy of both clozapine and risperidone on psychopathologic and neurocognitive measures in a prospective 12-week open-label trial in treatment-refractory schizophrenic patients from state psychiatric hospitals.. Thirty-five DSM-IV schizophrenic patients with a documented history of nonresponse to typical neuroleptics were treated with either clozapine or risperidone. Response was assessed every 2 weeks by independent raters with the Positive and Negative Syndrome Scale (PANSS), the Clinical Global Impressions (CGI) scale, neurologic rating scales, and plasma drug levels. Neurocognitive tests were administered at baseline and week 12.. Both clozapine and risperidone brought about significant (p < .003) overall improvement in psychopathology. However, clozapine was numerically superior to risperidone on PANSS total scores and PANSS positive, negative, excitement, and cognitive factors. Extrapyramidal side effects were minimal for clozapine, whereas some were present for risperidone. Patients taking risperidone improved significantly in the beginning stages of the study and remained stable thereafter. Patients taking clozapine showed a gradual improvement that occurred over the entire length of the trial. Neurocognitive measures showed minimal improvement and did not differentiate between the 2 medication groups.. Both clozapine and risperidone were comparably effective across a wide spectrum of psychopathologic measures. While the efficacy of clozapine was only numerically superior to that of risperidone, it was associated with fewer extrapyramidal side effects and with progressive improvement over the 12-week treatment period, suggesting that in longer trials clozapine may prove to be superior to risperidone in neuroleptic-refractory patients.

    Topics: Adult; Basal Ganglia Diseases; Clozapine; Cognition Disorders; Female; Humans; Male; Middle Aged; Neuropsychological Tests; Prospective Studies; Psychiatric Status Rating Scales; Risperidone; Schizophrenia; Schizophrenic Psychology; Treatment Outcome

1998
D2-dopamine receptor occupancy measured by IBZM-SPECT in relation to extrapyramidal side effects.
    Pharmacopsychiatry, 1998, Volume: 31, Issue:5

    The purpose of this study was to compare striatal D2 dopamine receptor occupancy of various typical neuroleptics and clozapine in relation to the occurrence of extrapyramidal side effects (EPS). Forty-four inpatients with schizophrenia, including 12 patients with schizodominant schizoaffective disorder, were evaluated using 123I-iodobenzamide (IBZM) and single photon emission computed tomography. Striatal D2 dopamine receptor occupancy was estimated by use of a striatal/frontal cortex ratio (ST/FC) of IBZM binding. Fourteen patients were neuroleptic-free and served as controls. Six patients were treated with clozapine and 24 patients were treated with various typical neuroleptics. ST/FC ratios in patients taking typical neuroleptics were significantly lower than those who were neuroleptic free or treated with clozapine. Patients with EPS had lower ST/FC ratios than those without EPS. A significant linear relationship between ST/FC ratios and severity of EPS estimated by the Simpson-Angus-Scale was established (r=-0.51, p=0.041).

    Topics: Adult; Antipsychotic Agents; Basal Ganglia Diseases; Benzamides; Clozapine; Dose-Response Relationship, Drug; Female; Frontal Lobe; Humans; Male; Neostriatum; Pyrrolidines; Radiopharmaceuticals; Receptors, Dopamine D2; Schizophrenia; Tomography, Emission-Computed, Single-Photon

1998
Clozapine treatment for neuroleptic-induced tardive dyskinesia, parkinsonism, and chronic akathisia in schizophrenic patients.
    The Journal of clinical psychiatry, 1997, Volume: 58, Issue:7

    Previous studies on the use of clozapine in neuroleptic-resistant chronic schizophrenic patients have demonstrated positive effects on tardive dyskinesia but were less conclusive about chronic akathisia and parkinsonism. The aim of the present study was to investigate the short-term (18 weeks) efficacy of clozapine in neuroleptic-resistant chronic schizophrenic patients with coexisting tardive dyskinesia, chronic akathisia, and parkinsonism.. Twenty chronic, neuroleptic-resistant schizophrenic patients with coexisting tardive dyskinesia, parkinsonism, and chronic akathisia were treated with clozapine. Assessment of tardive dyskinesia, parkinsonism, and chronic akathisia was made once weekly for 18 weeks with the Abnormal Involuntary Movement Scale (AIMS), Simpson-Angus Rating Scale for Extrapyramidal Side Effects, and Barnes Rating Scale for Drug-Induced Akathisia (BAS).. At the end of 18 weeks of clozapine treatment, improvement rates were 74% for tardive dyskinesia, 69% for parkinsonism, and 78% for chronic akathisia. A statistically significant reduction in the scores on the AIMS and Simpson-Angus Scale was achieved at Week 5 and on the BAS at Week 6 (p < .0001).. Relatively low doses of clozapine are effective for the treatment of neuroleptic-induced extrapyramidal syndromes in neuroleptic-resistant chronic schizophrenic patients. The relief of tardive dyskinesia, parkinsonism, and chronic akathisia in this group of patients occurs more rapidly than the reduction in psychotic symptoms. Disturbing, long-term extrapyramidal syndromes in chronic schizophrenic patients should be considered an indication for clozapine treatment.

    Topics: Adult; Akathisia, Drug-Induced; Antipsychotic Agents; Basal Ganglia Diseases; Chronic Disease; Clozapine; Comorbidity; Drug Administration Schedule; Dyskinesia, Drug-Induced; Female; Humans; Male; Parkinson Disease, Secondary; Psychiatric Status Rating Scales; Schizophrenia; Schizophrenic Psychology; Treatment Outcome

1997
Clozapine versus typical antipsychotics. A retro- and prospective study of extrapyramidal side effects.
    Psychopharmacology, 1996, Volume: 124, Issue:1-2

    Schizophrenic patients in long-term neuroleptic monotherapy with clozapine (n = 100) and perphenazine, flupenthixol or zuclopentixol (controls, n = 100) were evaluated for extrapyramidal side effects (EPS) (blind) as well as other side effects and mental condition (non-blind). In both groups the patients had received neuroleptic treatment for a total of 14 years (median) and the present antipsychotic (clozapine or control drug) for 5 years. Thus the clozapine-treated patients had previously received traditional neuroleptics for 9 years (median). The study was both retrospective (0.3-19 years for clozapine, 0.3-24 years for control drug, by means of chart information) and prospective (1 year, with video-controlled evaluation of EPS). There was a significantly lower prevalence of tardive dyskinesia (TD) in clozapine treated patients than control patients, although prior to this treatment there were more TD patients in the clozapine group (P < 0.05). This lower level of TD in the clozapine group was related to a lower induction of new cases (P < 0.001) and a tendency towards greater disappearance of TD in the clozapine than in the control group (P = 0.07). Clozapine treated patients without TD had started clozapine and ceased traditional neuroleptics at an earlier age than those with TD. Parkinsonian signs were seen in 33% of the clozapine patients versus 61% of the control patients, mainly as hypokinesia; tremor in 3% versus 11% and rigidity in 0 versus 19%. Psychic akathisia was found in 14% versus 40% and motor akathisia in 7% versus 29% of the patients, all differences significantly in favor of clozapine. Clozapine treated patients also had less neuroleptic-induced emotional indifference and depression, but more autonomic side effects than controls.

    Topics: Adult; Aged; Antipsychotic Agents; Basal Ganglia Diseases; Clozapine; Female; Flupenthixol; Humans; Male; Middle Aged; Perphenazine; Prospective Studies; Schizophrenia

1996
Extrapyramidal side effects of clozapine and haloperidol.
    Psychopharmacology, 1995, Volume: 118, Issue:1

    Neuroleptic-induced extrapyramidal side effects (EPS) were evaluated in 92 patients treated with clozapine for the first time and 59 patients treated with haloperidol followed in a drug monitoring program. Side effects were measured by the Columbia University Rating Scale, the Simpson Dyskinesia Scale and the Hillside Akathisia Scale. The cumulative incidence rate for tremor was found to be 24.4% in the clozapine group and 39.3% in the haloperidol group. This did not amount to a statistically significant group difference. Bradykinesia was observed in 21.8% of the patients treated with clozapine and in 47.7% of the patients of haloperidol (P = 0.011). In the clozapine group the akathisia incidence rate was 5.6%, whereas haloperidol patients showed a higher rate of 31.7% (P = 0.005). Our results show higher incidence rates of tremor and bradykinesia during clozapine treatment than previous studies. We conclude that clozapine is not entirely free of EPS, but they are usually less severe and of a different quality than side effects induced by typical antipsychotics.

    Topics: Adult; Akathisia, Drug-Induced; Basal Ganglia Diseases; Clozapine; Dyskinesia, Drug-Induced; Female; Haloperidol; Humans; Male; Tremor

1995
Risperidone versus clozapine in the treatment of schizophrenic patients with acute symptoms: a double blind, randomized trial.
    Progress in neuro-psychopharmacology & biological psychiatry, 1994, Volume: 18, Issue:1

    1. In order to verify the hypothesis that risperidone is a useful therapeutic alternative to clozapine the authors carried out a randomized double blind trial in 59 patients with paranoid hallucinatory psychoses. 2. In a treatment lasting 28 days three groups of patients received either 4 mg risperidone (N = 20), 8 mg risperidone (N = 19), or 400 mg clozapine (N = 20) daily. 3. The tolerance of 4 mg risperidone was globally assessed as being better than that of 400 mg clozapine. Drop-outs under clozapine were mostly caused by side effects, whereas under risperidone they tended to occur for therapeutic inefficacy. 4. The antipsychotic effect was highly significant and clinically relevant under both risperidone and clozapine.

    Topics: Acute Disease; Adult; Aged; Antipsychotic Agents; Basal Ganglia Diseases; Clozapine; Double-Blind Method; Electrocardiography; Electroencephalography; Female; Humans; Infant, Newborn; Isoxazoles; Male; Middle Aged; Piperidines; Psychiatric Status Rating Scales; Risperidone; Schizophrenia, Paranoid

1994
Predictors of clozapine response in schizophrenia.
    The Journal of clinical psychiatry, 1994, Volume: 55 Suppl B

    The introduction of the atypical neuroleptic, clozapine, has had widespread influence not only on the treatment of the seriously mentally ill patient, but also on new drug development and on hypotheses of the pathophysiology of schizophrenia. While clozapine differs from traditional neuroleptics in its lack of extrapyramidal side effects (EPS), it also is distinct in its profile of neurotransmitter receptor affinities. In our work examining the clinical and biological effects of clozapine in patients with schizophrenia, we have identified the presence of EPS during typical neuroleptic treatment as a consistent predictor of subsequent good response to clozapine. Further, our data suggest that clozapine should not be reserved for the most chronically ill patients, but rather be utilized in patients with less chronic courses of schizophrenia. Biological predictors of clozapine response are consistent with dopaminergic, serotonergic, and noradrenergic facets to its mechanism of action.

    Topics: Adult; Antipsychotic Agents; Basal Ganglia Diseases; Clozapine; Double-Blind Method; Female; Fluphenazine; Homovanillic Acid; Humans; Hydroxyindoleacetic Acid; Male; Probability; Receptors, Neurotransmitter; Schizophrenia; Treatment Outcome

1994
The tolerability and efficacy of the atypical neuroleptic remoxipride compared with clozapine and haloperidol in acute schizophrenia.
    Acta psychiatrica Scandinavica. Supplementum, 1994, Volume: 380

    Remoxipride and clozapine are new neuroleptics that are thought to be superior to the substances in use by their efficacy and tolerance. At the University Clinic of Psychiatry in DĂĽsseldorf a double-blind study with 54 patients diagnosed as schizophrenic in accordance with DSM-III was conducted to record the influence of the neuroleptics remoxipride, clozapine and haloperidol on schizophrenic psychosis. The schizophrenic symptoms were rated by the AMDP-system (Arbeitsgemeinschaft fĂĽr Methodik und Dokumentation in der Psychiatrie), Brief Psychiatric Rating Scale and the Clinical Global Impression on days 0, 7, 14, 21 and 28 of treatment to evaluate the degree of change in psychopathology. The tolerance of the neuroleptic treatment was checked by the doctor's overall impression and the somatic findings of the AMDP-system. All 3 neuroleptics reduced the schizophrenic symptoms to a similar degree but showed differentiation as to their side effects.

    Topics: Adult; Basal Ganglia Diseases; Clozapine; Cognition; Double-Blind Method; Drug Tolerance; Emotions; Female; Haloperidol; Humans; Male; Neurologic Examination; Psychiatric Status Rating Scales; Remoxipride; Schizophrenia; Schizophrenic Psychology; Treatment Outcome

1994
Update on the clinical efficacy and side effects of clozapine.
    Schizophrenia bulletin, 1991, Volume: 17, Issue:2

    Clozapine (CLOZ) is an atypical antipsychotic drug being used with increasing frequency throughout the world and has recently been commercially marketed in the United States. Its unique properties make it a promising but challenging drug to use in the treatment of schizophrenia. In order to use CLOZ most effectively and efficiently, clinicians must be aware of its potential benefits and risks. This report is a review and critical evaluation of current knowledge regarding the clinical efficacy and side effects of CLOZ. Although CLOZ has proven to be effective in some treatment-refractory schizophrenic patients and to produce relatively few extrapyramidal side effects compared to classical neuroleptic drugs, several issues require further investigation including what defines neuroleptic intolerance, the optimal dose range, and the appropriate duration of a CLOZ treatment trial. Similarly, studies are needed to determine what role CLOZ should have in the treatment of patients with predominantly negative symptoms and those patients who are only partially responsive to standard neuroleptics. In addition, important questions remain as to what other conditions might be indications for CLOZ, for example, schizoaffective disorder, affective psychoses, and idiopathic Parkinson's disease.

    Topics: Agranulocytosis; Basal Ganglia Diseases; Clozapine; Humans; Nervous System; Schizophrenia

1991
Treatment outcome with clozapine in tardive dyskinesia, neuroleptic sensitivity, and treatment-resistant psychosis.
    The Journal of clinical psychiatry, 1987, Volume: 48, Issue:7

    Thirty-eight chronically ill psychotic patients were treated with clozapine for indications of tardive dyskinesia, severe extrapyramidal side effects caused by other neuroleptics, or treatment-resistant psychosis. Fifty-five percent of all patients and 40% of schizophrenics improved with clozapine. Abnormal involuntary movements were suppressed during treatment and, with 1 exception, returned to baseline levels after clozapine was discontinued. Our results support the conclusion that clozapine's efficacy in refractory cases and its lack of neurological side effects make it a unique neuroleptic with advantages over conventional antipsychotic agents. The drug appears to be safe when treatment is accompanied by frequent clinical and hematologic monitoring.

    Topics: Adolescent; Adult; Aged; Antipsychotic Agents; Basal Ganglia Diseases; Clinical Trials as Topic; Clozapine; Dibenzazepines; Dyskinesia, Drug-Induced; Female; Humans; Male; Middle Aged; Outcome and Process Assessment, Health Care; Psychiatric Status Rating Scales; Psychotic Disorders; Schizophrenia

1987
The risks and benefits of clozapine versus chlorpromazine.
    Journal of clinical psychopharmacology, 1987, Volume: 7, Issue:6

    Clozapine is an atypical antipsychotic drug with reduced risk of unwanted neurological effects in comparison with other drugs. In this multicenter study, 151 hospitalized schizophrenic patients were randomly assigned to treatment under double-blind conditions to assess the antipsychotic efficacy and safety of clozapine versus chlorpromazine. All patients exhibited tardive dyskinesia or other extrapyramidal side effects associated with at least two prior neuroleptics. Eleven patients were dropped from treatment due to extrapyramidal symptoms while being treated with chlorpromazine; only one clozapine patient's treatment was terminated for this reason. Clozapine patients exhibited clinical improvement superior to that of chlorpromazine patients as assessed by the Brief Psychiatric Rating and Clinical Global Impression scales. These results suggest that clozapine is well tolerated and may be therapeutically superior to chlorpromazine in treating psychotic behavior. Agranulocytosis potential can be minimized by frequent white blood cell counts and removing nonresponding patients from treatment prior to the peak risk period (months 2 through 6).

    Topics: Adult; Basal Ganglia Diseases; Chlorpromazine; Clinical Trials as Topic; Clozapine; Dibenzazepines; Double-Blind Method; Female; Humans; Male; Middle Aged; Psychiatric Status Rating Scales; Random Allocation; Risk Factors; Schizophrenia

1987
[Influence of clozapine on neuroleptigenic extrapyramidal motor disturbances (author's transl)].
    Arzneimittel-Forschung, 1978, Volume: 28, Issue:9

    1. Human neuroleptogenic EPMS-disturbances are reversed by clozapine in animal experiments and in clinical use. This is consistent with the central anticholinergic efficacy of clozapine. 2. Clozapine seems to be a favourable concomitant medication when high dosage therapy of neuroleptics is applied--or at the incidence of dyskinesia.

    Topics: Adolescent; Adult; Antipsychotic Agents; Basal Ganglia Diseases; Clinical Trials as Topic; Clozapine; Dibenzazepines; Dyskinesia, Drug-Induced; Female; Humans; Male; Parkinson Disease; Placebos

1978
Extrapyramidal reactions and amine metabolites in cerebrospinal fluid during haloperidol and clozapine treatment of schizophrenic patients.
    Psychopharmacologia, 1975, Volume: 40, Issue:4

    8 male schizophrenic patients participated in a double-blind, cross over study of the extrapyramidal side-effects of haloperidol and clozapine (acute dystonis, Parkinsonism and tardive dyskinesia), together with their effect on homovanillic acid (HVA) and 5-hydroxyindoleacetic acid (5-HIAA) in the cerebrospinal fluid (CSF). Haloperidol (9 mg/day) caused Parkinsonism, reduced tardive dyskinesias and increased the HVA concentration in the CSF. Clozapine (225 mg/day) had no effect on the neurological phenomena but reduced HVA and 5-HIAA concentrations in the CSF. During the discontinuation phase following the administration of haloperidol, tardive dyskinesia occurred or was aggravated; this did not occur after administration of clozapine. Accordingly, it is suggested that clozapine does not induce dopaminergic hypersensibility and, therefore, will not induce tardive dyskinesias.

    Topics: Adult; Aged; Basal Ganglia Diseases; Clinical Trials as Topic; Clozapine; Dibenzazepines; Haloperidol; Homovanillic Acid; Humans; Hydroxyindoleacetic Acid; Male; Middle Aged; Movement Disorders; Parkinson Disease, Secondary; Phenylacetates; Schizophrenia

1975

Other Studies

71 other study(ies) available for clozapine and Basal-Ganglia-Diseases

ArticleYear
[Psychotic disorder induced by Fahr's syndrome: a case report].
    L'Encephale, 2014, Volume: 40, Issue:3

    Fahr's syndrome is a rare disorder characterized by abnormal deposits of calcium in areas of the brain that control movement, including the basal ganglia and the cerebral cortex associated with many neurological and psychiatric abnormalities such as a rigid hypokinetic syndrome, mood disorders and cognitive impairment. Fahr's syndrome is secondary to some disorders, such as hypoparathyroidism.. We report the case of a 56 year-old man, with a history of cataract, who was admitted to our psychiatric hospital for the first time in his life because of psychotic symptoms associated with irritability and aggressiveness. Since the age of 38 the patient had become nervous, 10 years later he developed tonic-clonic seizures. Two months ago, he began expressing delusions of persecution against his wife and sons and making fugues. According to his family during this period, he was agitated, aggressive, and suffered from insomnia and anorexia. The general and psychiatric examination showed an upright and bronzed patient with neglected hygiene. He was indifferent to his environment and expressed poor mimics and gestures. He was anxious, suspicious and not very talkative. He was conscious but his attention was slightly decreased. Moreover, he was not aware of his problems. The neurological examination showed extrapyramidal syndrome with postural tremor and cerebellar ataxia. A cranial computed tomography brain scan found bilateral, symmetric basal ganglia calcifications, in favour of Fahr's syndrome. Phosphocalcic investigations revealed low concentration of serum calcium at 1.01mmol/L (normal 2.15 to 2.57mmol/L) and hyperphosphoremia at 2.69mmol/L (normal 0.81 to 1.55mmol/L). He also had low concentrations of 25-OH vitamin as well as decreased urinary levels of phosphate and calcium. The blood level of parathyroid hormone was 0ng/L. The diagnosis of Fahr's syndrome, revealing a hypoparathyroidism was posed. He was supplemented with calcium and alpha cholecalciferol and treated with clozapine (100mg per day). After four weeks, psychotic symptoms responded well to this treatment without expressing any side effects, notably seizures.. Psychotic symptoms seen in Fahr's disease include auditory and visual hallucinations, complex perceptual distortions, delusions, and fugue state. Some of them were manifest in this patient. It is likely that the psychosis in both Fahr's disease and schizophrenia share a similar pathology. Positive psychotic symptoms, hallucinations, and paranoia are not necessarily generated by the classical hypothesis of dopamine-mediated attachment of salience to internally generated stimuli. Still, there is some evidence that disruption of the cortex involved in the pathophysiology of schizophrenia is also seen in Fahr's disease, particularly in areas of the limbic system.. Psychiatrists should consider Fahr's syndrome as a differential diagnosis in the evaluation of psychosis associated with seizures. This case, along with others in the literature, further emphasizes the importance of the role of neuro-imaging and the search for disrupted phosphocalcic metabolism in patients with atypical psychotic symptoms. Moreover, further research should focus on pharmacologic interventions. The efficacy and risks of neuropharmacologic and psychopharmacologic interventions in Fahr's syndrome, and correlates of good and poor outcome with these interventions remain to be defined.

    Topics: Basal Ganglia; Basal Ganglia Diseases; Brain Diseases; Calcinosis; Calcium; Cholecalciferol; Clozapine; Humans; Hypoparathyroidism; Male; Middle Aged; Neurocognitive Disorders; Neurodegenerative Diseases; Tomography, X-Ray Computed

2014
Pharacogenetic effects of dopamine transporter gene polymorphisms on response to chlorpromazine and clozapine and on extrapyramidal syndrome in schizophrenia.
    Progress in neuro-psychopharmacology & biological psychiatry, 2010, Aug-16, Volume: 34, Issue:6

    A number of studies have investigated the effectiveness of the dopamine transporter (SLC6A3) Gene as an antipsychotic target. However, the focus has mainly been on a 40-bp variable number of a tandem repeat (VNTR) in the 3'-region and results have been inconsistent. To fully evaluate SLC6A3 as a therapeutic antipshycotic target we investigated association of the gene with responses to chlorpromazine and clozapine and with chlorpromazine-induced extrapyramidal syndrome (EPS) in the Chinese schizophrenia population. Six polymorphisms across the whole region of this gene were analyzed, namely rs2652511 (T-844C) and rs2975226 (T-71A) in the 5'-regulatory region, rs2963238 (A1491C) in intron 1, a 30-bp VNTR in intron 8, rs27072 and the 40-bp VNTR in the 3'-region. We found that the polymorphic marker, rs2975226, showed significant association of allele and genotype frequencies with response to clozapine (allele-wise: adjusted p=0.00404; genotype-wise: adjusted p=0.024), and that patients with the T allele had a better response to the drug. The haplotype block constructed from the first three markers near the 5'-region showed significant association with response to clozapine (for haplotype T-T-A: p=0.0085; for haplotype C-A-C: p=0.0092). We did not identify any significant association of the six genetic variants or haplotypes with EPS after Bonferoni correction. Our findings suggest that the 5'-regulatory region of SLC6A3 plays an important role in response to clozapine and that its role in EPS needs to be replicated in a large-scale well designed study.

    Topics: Adult; Antipsychotic Agents; Basal Ganglia Diseases; Chlorpromazine; Clozapine; Dopamine Plasma Membrane Transport Proteins; Female; Gene Frequency; Genetic Association Studies; Genetic Predisposition to Disease; Genotype; Haplotypes; Humans; Male; Middle Aged; Pharmacogenetics; Polymerase Chain Reaction; Polymorphism, Single Nucleotide; Schizophrenia; Treatment Outcome

2010
Clozapine-induced tardive dyskinesia in schizophrenic patients taking clozapine as a first-line antipsychotic drug.
    The world journal of biological psychiatry : the official journal of the World Federation of Societies of Biological Psychiatry, 2009, Volume: 10, Issue:4 Pt 3

    Clozapine causes few extrapyramidal symptoms and is recommended as a treatment drug for severe tardive dyskinesia (TD). However, several case reports have suggested that clozapine could also cause TD. We investigated whether clozapine used as a first-line antipsychotic drug can cause TD.. We identified 101 patients at Yanbian Socio-Mental Hospital and Yanbian Brain Hospital in China who had received clozapine as a primary antipsychotic drug since their first episode of illness and evaluated the prevalence rate, type, and severity of TD using the Extrapyramidal Symptoms Rating Scale (ESRS). The criterion for TD was a score of > or = 3 on one item or 2 on two or more items of the ESRS.. The mean age and duration of illness of the patients were 38.93+/-8.36 and 12.88+/-6.90 years, respectively. The mean duration of clozapine treatment was 12.10+/-6.26 years. The prevalence of TD was 3.96% (4/101). Compared to patients without TD, patients with TD had a long duration of illness and clozapine treatment; all had the orolingual type of TD. TD was relatively mild, with a mean score of 4.75, and tended to accentuate with an activation procedure of rapid pronation and supination of the hands.. These results suggest that clozapine may cause TD; however, the prevalence is low and the severity is relatively mild, with no or mild self-reported discomfort. Therefore, we recommend that regular examination for TD using the activation procedure should be performed in patients who use clozapine on a long-term basis.

    Topics: Adult; Antipsychotic Agents; Basal Ganglia Diseases; China; Clozapine; Drug Administration Schedule; Dyskinesia, Drug-Induced; Female; Humans; Male; Middle Aged; Prevalence; Reactive Oxygen Species; Schizophrenia; Severity of Illness Index; Surveys and Questionnaires

2009
Combined low-dose clozapine with low-dose aripiprazole in a schizophrenic patient.
    Journal of psychopharmacology (Oxford, England), 2009, Volume: 23, Issue:1

    Aripiprazole, a partial dopaminergic agonist, represents a well-tolerated and effective addition to the antipsychotic armamentarium. However, accumulated data indicates that aripiprazole may still induce extrapyramidal side effects (EPS) in susceptible patients. Guidelines for treating schizophrenia have consistently recommended antipsychotic monotherapy. Nevertheless, in certain clinical situations, a thorough evaluation of the benefit/risk ratio suggests that combinations of antipsychotic agents may improve treatment efficacy and tolerability. We report a schizophrenic patient for whom sequential administration of aripiprazole and risperidone induced severe EPS, and subsequent combination therapy with of clozapine and aripiprazole achieved adequate symptom control and markedly reduced EPS.

    Topics: Adult; Antipsychotic Agents; Aripiprazole; Basal Ganglia Diseases; Clozapine; Dose-Response Relationship, Drug; Drug Therapy, Combination; Guidelines as Topic; Humans; Male; Piperazines; Quinolones; Risk Assessment; Risperidone; Schizophrenia

2009
Evolution of neuroleptic-induced extrapyramidal syndromes under long-term neuroleptic treatment.
    Schizophrenia research, 2008, Volume: 100, Issue:1-3

    The long-term evolution of neuroleptic-induced extrapyramidal syndromes (EPS) of Parkinsonism, akathisia and tardive dyskinesia (TD) is still a controversial issue worth exploring.. A total of 200 inpatients on regular typical neuroleptics (NL) and/or clozapine were assessed in 1995 with regard to the prevalence of EPS. Altogether, 83 patients could be reassessed in 2003/04 (63 had died) using the same methods. Strict definitions of EPS were used. The complete account of NL therapy the patients were prescribed between 1995 and 2003/04 (including atypical NL other than clozapine) was considered.. The prevalences found in 1995 and 2003/04 were 17% and 29% for Parkinsonism, 14% and 14% for akathisia, and 24% and 13% for TD. There were considerable intra-individual fluctuations in EPS occurrence even when the overall prevalence rate remained the same. In intra-individual comparisons of EPS ratings on both assessments, there was a tendency for worsening of Parkinsonism to be associated with a current (2003/04) therapy with typical NL; worsening of akathisia was associated with a current therapy with atypical NL other than clozapine, amelioration of akathisia with a current therapy with clozapine; and, basically, there were no significant associations found between the changes in TD ratings and the long-term therapy with typical NL, clozapine, and other atypical NL, considering cumulative doses of all these drugs. In a multivariate analysis, there was a tendency for the long-term evolution of TD to depend on illness duration as the only variable.. There are intra-individual fluctuations in all EPS over longer time periods. The choice of current NL therapy has an impact on Parkinsonism and akathisia. The long-term evolution of TD appears independent of NL prescriptions.

    Topics: Adult; Akathisia, Drug-Induced; Antipsychotic Agents; Basal Ganglia Diseases; Clozapine; Dyskinesias; Female; Follow-Up Studies; Hospitalization; Humans; Longitudinal Studies; Male; Middle Aged; Neurologic Examination; Parkinsonian Disorders; Patient Dropouts; Prevalence; Psychotic Disorders; Schizophrenia; Schizophrenic Psychology

2008
What CATIE did: some thoughts on implications deep and wide.
    Psychiatric services (Washington, D.C.), 2008, Volume: 59, Issue:5

    The author discusses five lessons that can be learned from the seminal results of the Clinical Antipsychotic Trials of Intervention Effectiveness (CATIE). The lessons extend beyond practice implications to fundamental questions about how psychopharmacology studies are conducted and how results are interpreted and given relevance in regard to prescribing. The author recounts the history of the term "atypical" and how it came to be understood in the context of antipsychotics. The error of using high-dose haloperidol as a comparator in assessments of new antipsychotics -- and of generalizing from the results of these studies -- is also discussed. The CATIE results force uncomfortable questions about the extent of knowledge concerning the clinical pharmacology of a major treatment modality, which the author illustrates by examining possible reasons for the differential clinical actions of clozapine. The author concludes that CATIE benefited both patients and clinicians by opening up to patients the full gamut of antipsychotics for treatment planning and by reinstating to physicians their key skill in expert, individualized prescribing.

    Topics: Antipsychotic Agents; Basal Ganglia Diseases; Clinical Trials as Topic; Clozapine; Drug Administration Schedule; Drug Prescriptions; Haloperidol; Health Planning Guidelines; Humans; Schizophrenia

2008
Principal component analysis differentiates the receptor binding profiles of three antipsychotic drug candidates from current antipsychotic drugs.
    Journal of medicinal chemistry, 2007, Oct-18, Volume: 50, Issue:21

    The receptor binding affinities of the three drug candidates 1 (SLV310), 2 (SLV313), and 3 (SLV314) were positioned against the results from nine (a)typical antipsychotic drugs. The receptor binding data from sixteen monoaminergic receptors served as the input in a principal component analysis (PCA). The PCA outcome revealed a unique binding profile of 1, 2, and 3 as compared with the reference compounds 4-8 and 10-12. The weight gain inducing antipsychotics 6-8 clustered in the PCA by scoring strongly negative for factor 1. The hyperprolactinaemia related antipsychotics 4, 5, 10, and 12 clustered by their negative scores for factor 2.

    Topics: Antipsychotic Agents; Basal Ganglia Diseases; Benzoxazines; Biogenic Monoamines; Humans; Hyperprolactinemia; Indoles; Metabolic Diseases; Phthalimides; Piperazines; Principal Component Analysis; Pyridines; Radioligand Assay; Receptors, Biogenic Amine; Weight Gain

2007
First- and second-generation antipsychotics: learning from CUtLASS and CATIE.
    Archives of general psychiatry, 2007, Volume: 64, Issue:8

    Topics: Antipsychotic Agents; Basal Ganglia Diseases; Clozapine; Humans; Mood Disorders; Neuroleptic Malignant Syndrome; Randomized Controlled Trials as Topic; Schizophrenia; Treatment Outcome

2007
The Texas Medication Algorithm Project antipsychotic algorithm for schizophrenia: 2006 update.
    The Journal of clinical psychiatry, 2007, Volume: 68, Issue:11

    A panel of academic psychiatrists and pharmacists, clinicians from the Texas public mental health system, advocates, and consumers met in June 2006 in Dallas, Tex., to review recent evidence in the pharmacologic treatment of schizophrenia. The goal of the consensus conference was to update and revise the Texas Medication Algorithm Project (TMAP) algorithm for schizophrenia used in the Texas Implementation of Medication Algorithms, a statewide quality assurance program for treatment of major psychiatric illness.. Four questions were identified via premeeting teleconferences. (1) Should antipsychotic treatment of first-episode schizophrenia be different from that of multiepisode schizophrenia? (2) In which algorithm stages should first-generation antipsychotics (FGAs) be an option? (3) How many antipsychotic trials should precede a clozapine trial? (4) What is the status of augmentation strategies for clozapine? Subgroups reviewed the evidence in each area and presented their findings at the conference.. The algorithm was updated to incorporate the following recommendations. (1) Persons with first-episode schizophrenia typically require lower antipsychotic doses and are more sensitive to side effects such as weight gain and extrapyramidal symptoms (group consensus). Second-generation antipsychotics (SGAs) are preferred for treatment of first-episode schizophrenia (majority opinion). (2) FGAs should be included in algorithm stages after first episode that include SGAs other than clozapine as options (group consensus). (3) The recommended number of trials of other antipsychotics that should precede a clozapine trial is 2, but earlier use of clozapine should be considered in the presence of persistent problems such as suicidality, comorbid violence, and substance abuse (group consensus). (4) Augmentation is reasonable for persons with inadequate response to clozapine, but published results on augmenting agents have not identified replicable positive results (group consensus).. These recommendations are meant to provide a framework for clinical decision making, not to replace clinical judgment. As with any algorithm, treatment practices will evolve beyond the recommendations of this consensus conference as new evidence and additional medications become available.

    Topics: Algorithms; Antipsychotic Agents; Basal Ganglia Diseases; Clozapine; Drug Therapy; Humans; Mental Health Services; Schizophrenia; Substance-Related Disorders; Suicide, Attempted; Texas; Violence; Weight Gain

2007
[A naturalistic, observational study of outpatients with schizophrenia: efficacy and safety results after 6 months. The International Schizophrenia Outpatient Health Outcomes study, IC-SOHO].
    Neuropsychopharmacologia Hungarica : a Magyar Pszichofarmakologiai Egyesulet lapja = official journal of the Hungarian Association of Psychopharmacology, 2007, Volume: 9, Issue:3

    The International Schizophrenia Outpatient Health Outcomes study, IC-SOHO is a three-year international observational study that investigates clinical and health outcomes of antipsychotic treatments. 7658 outpatients treated for schizophrenia were enrolled in the study, who needed an antipsychotic therapy to initiate or switch. The primary analysis compared the group taking olanzapine with the group taking any other antipsychotics, while the secondary comparison was performed between those treated with olanzapine and those with risperidone. Efficacy analysis was carried out based on changes in Clinical Global Impression of Severity scale (CGI-S), which was performed at a global symptom level, as well as with respect to the patients' positive, negative, cognitive and depressive symptoms. In addition, adverse events were also evaluated. Results of the analysis of the 3- and 6-month data from Hungary are disclosed in this publication. 200 patients were enrolled in the country. Demographics of the treatment groups were not significantly different. At 3 and 6 months after treatment initiation, there were no significant between-group differences in improvement of global symptomatology, however, cognitive symptoms improved more in the Olanzapine-group compared to those taking other antipsychotics (p<0.05). In patients showing Extrapyramidal Symptoms (EPS) at baseline, these symptoms finished to a greater extent among those receiving olanzapine than in those receiving other antipsychotics (after 6 months D<0.0001). Half a year later, significantly less patients showed extrapyramidal adverse events (p=0,0007), and the previous EPS terminated to a greater extent (p=0.0016) in the olanzapine group, as compared to those taking risperidone. No between-group differences were found in changes of sexual functions, as well as of weight and Body Mass Index measures. Switching antipsychotic initiated at study baseline, and adding-on one or more other antipsychotic to the initial one, were significantly less frequent in the Olanzapine-group compared to those initiated other antipsychotics. In the first 3 months, treatment compliance was significantly higher with olanzapine therapy than with other antipsychotic treatments, and with risperidone respectively. Results from the Hungarian sample correspond with results from higher analysis levels of wider patient populations of IC-SOHO study. Olanzapine showed outstanding efficacy in lessening cognitive disturbances and global cli

    Topics: Adult; Aggression; Antipsychotic Agents; Basal Ganglia Diseases; Benzodiazepines; Clozapine; Dibenzothiazepines; Erectile Dysfunction; Female; Galactorrhea; Gynecomastia; Haloperidol; Humans; Hungary; International Cooperation; Libido; Male; Menstruation Disturbances; Middle Aged; Olanzapine; Outpatients; Patient Admission; Patient Compliance; Prospective Studies; Quetiapine Fumarate; Risperidone; Schizophrenia; Schizophrenic Psychology; Severity of Illness Index

2007
Increased risk of extrapyramidal side-effect treatment associated with atypical antipsychotic polytherapy.
    Acta psychiatrica Scandinavica, 2006, Volume: 113, Issue:2

    To determine whether atypical antipsychotic polytherapy is a risk factor for drug treatment for extrapyramidal side-effects (anti-EPS drugs) and whether the risk is attributable to antipsychotic dose.. We studied Iowa Medicaid beneficiaries aged 18-64 years with an active atypical and no conventional antipsychotic on January 1, 2001. The association of atypical antipsychotic polytherapy with anti-EPS drug treatment was determined. Multiple logistic regression was utilized to adjust for covariates in two models, the first adjusting for age, sex and the specific antipsychotic(s) prescribed, and the second also adjusting for doses.. Among 4400 patients, the unadjusted odds of anti-EPS treatment were increased two-fold with polytherapy. Polytherapy remained a risk factor in the first model (OR 1.5, 95% CI 1.1-2.0), but not after adjusting for doses (OR 1.0, 95% CI 0.7-1.4).. Atypical antipsychotic polytherapy is a risk factor for anti-EPS drug treatment, apparently because of higher cumulative doses.

    Topics: Adolescent; Adult; Antipsychotic Agents; Basal Ganglia Diseases; Benzodiazepines; Clozapine; Cross-Sectional Studies; Delayed-Action Preparations; Dibenzothiazepines; Drug Therapy, Combination; Female; Humans; Iowa; Male; Mathematical Computing; Medicaid; Middle Aged; Models, Statistical; Olanzapine; Product Surveillance, Postmarketing; Psychotic Disorders; Quetiapine Fumarate; Regression Analysis; Risk Factors; Risperidone; Statistics as Topic

2006
Comparative effectiveness of antipsychotic drugs. A commentary on: Cost Utility Of The Latest Antipsychotic Drugs In Schizophrenia Study (CUtLASS 1) and Clinical Antipsychotic Trials Of Intervention Effectiveness (CATIE).
    Archives of general psychiatry, 2006, Volume: 63, Issue:10

    Topics: Antipsychotic Agents; Basal Ganglia Diseases; Chlorpromazine; Clozapine; Cost-Benefit Analysis; Humans; Randomized Controlled Trials as Topic; Research Design; Schizophrenia; Schizophrenic Psychology; Treatment Outcome; United Kingdom; United States

2006
Selective prescribing of atypical antipsychotics.
    Pharmacoepidemiology and drug safety, 2005, Volume: 14, Issue:1

    The aim of the study was to investigate whether the most recent introduced atypical antipsychotics olanzapine and risperidone were preferentially prescribed to patients susceptible to develop extrapyramidal side effects (EPS) and those not responding adequately to typical antipsychotics.. Data were obtained from the Dutch PHARMO system that includes complete medication and hospital admission records of 675 000 residents of 14 Dutch cities. A total number of 129 new users of olanzapine and 142 new users of risperidone as well as 507 new users of typical antipsychotic drugs were identified from our database in the period of 1996-1998. The prevalence of markers of EPS, therapy resistance and therapy non-compliance were assessed in the period of 1 year prior to a new start of an antipsychotic.. New use of olanzapine and risperidone was significantly associated with previous use of other antipsychotics (odds ratio 4.0, 95%CI: 2.5-6.7 and odds ratio 3.0, 95%CI: 2.0-4.7, respectively). New use of olanzapine and risperidone was also associated with previous use of anticholinergic drugs compared to users of typical antipsychotics (over three and two times more, respectively). This effect diminished when adjusted for previous use of antipsychotics.. In particular olanzapine and also risperidone were selectively prescribed to patients formerly treated with other antipsychotics and to those susceptible for EPS. If not recognised or controlled for, observational studies comparing different antipsychotic drugs may produce biased results on efficacy or frequency of side effects for the different types of antipsychotics.

    Topics: Adult; Aged; Antipsychotic Agents; Basal Ganglia Diseases; Benzodiazepines; Cholinergic Antagonists; Clozapine; Delayed-Action Preparations; Disease Susceptibility; Drug Administration Schedule; Drug Monitoring; Drug Utilization Review; Female; Humans; Male; Medical Records, Problem-Oriented; Middle Aged; Netherlands; Olanzapine; Patient Selection; Pharmacoepidemiology; Risperidone; Treatment Outcome

2005
Lack of extrapyramidal side effects predicts quality of life in outpatients treated with clozapine or with typical antipsychotics.
    Psychiatry research, 2005, Feb-28, Volume: 133, Issue:2-3

    We compared symptom severity and quality of life (QOL) in schizophrenic patients adequately treated with typical antipsychotics (TAP) or clozapine (CZP). Groups did not differ in symptom severity or QOL. Clozapine caused fewer extrapyramidal symptoms. Negative and extrapyramidal symptoms predicted QOL. Similar outcome in both groups suggests a common ceiling to antipsychotic efficacy.

    Topics: Adult; Ambulatory Care; Antipsychotic Agents; Basal Ganglia Diseases; Clozapine; Female; Humans; Male; Predictive Value of Tests; Quality of Life; Schizophrenia

2005
Pharmacokinetic-pharmacodynamic analysis of antipsychotics-induced extrapyramidal symptoms based on receptor occupancy theory incorporating endogenous dopamine release.
    Drug metabolism and pharmacokinetics, 2005, Volume: 20, Issue:3

    We aimed to analyze the risks of extrapyramidal symptoms (EPS) induced by typical and atypical antipsychotic drugs using a common pharmacokinetic-pharmacodynamic (PK-PD) model based on the receptor occupancy. We collected the data for EPS induced by atypical antipsychotics, risperidone, olanzapine and quetiapine, and a typical antipsychotic, haloperidol from literature and analyzed the following five indices of EPS, the ratio of patients obliged to take anticholinergic medication, the occurrence rates of plural extrapyramidal symptoms (more than one of tremor, dystonia, hypokinesia, akathisia, extrapyramidal syndrome, etc.), parkinsonism, akathisia, and extrapyramidal syndrome. We tested two models, i.e., a model incorporating endogenous dopamine release owing to 5-HT2A receptor inhibition and a model not considering the endogenous dopamine release, and used them to examine the relationship between the D2 receptor occupancy of endogenous dopamine and the extent of drug-induced EPS. The model incorporating endogenous dopamine release better described the relationship between the mean D2 receptor occupancy of endogenous dopamine and the extent of EPS than the other model, as assessed by the final sum of squares of residuals (final SS) and Akaike's Information Criteria (AIC). Furthermore, the former model could appropriately predict the risks of EPS induced by two other atypical antipsychotics, clozapine and ziprasidone, which were not incorporated into the model development. The developed model incorporating endogenous dopamine release owing to 5-HT2A receptor inhibition may be useful for the prediction of antipsychotics-induced EPS.

    Topics: Antipsychotic Agents; Basal Ganglia Diseases; Benzodiazepines; Clozapine; Controlled Clinical Trials as Topic; Dibenzothiazepines; Haloperidol; Humans; Olanzapine; Piperazines; Quetiapine Fumarate; Receptor, Serotonin, 5-HT2A; Receptors, Dopamine D2; Risperidone; Schizophrenia; Thiazoles

2005
Pisa syndrome and atypical antipsychotics.
    The American journal of psychiatry, 2004, Volume: 161, Issue:2

    Topics: Aged; Aged, 80 and over; Antipsychotic Agents; Basal Ganglia Diseases; Clozapine; Depressive Disorder, Major; Dystonia; Female; Humans; Syndrome

2004
Attitudes of schizophrenia outpatients toward psychiatric medications: relationship to clinical variables and insight.
    The Journal of clinical psychiatry, 2004, Volume: 65, Issue:10

    Attitude toward medications is important for medication adherence. A patient's drug attitude probably reflects a weighing of benefits against experienced or anticipated side effects or risks associated with the medication. We predicted (1) that drug attitudes would be more positive among schizophrenia patients taking second-generation compared to first-generation antipsychotics because of their greater tolerability and efficacy; and (2) that greater insight into illness, fewer extrapyramidal symptoms, and better social functioning would be associated with better attitudes toward psychiatric medication.. In a cross-sectional study of 81 DSM-IV-diagnosed schizophrenia outpatients, we used multivariate analysis to determine clinical and demographic predictors of drug attitude. Drug attitude was assessed with the 10-item Drug Attitude Inventory (DAI). The relationship between the DAI and psychopathology, insight, extrapyramidal symptoms, level of functioning, and type of antipsychotic (first-generation versus second-generation versus clozapine) was examined.. Less awareness of current symptoms, presence of deficit symptoms, and employment predicted a negative attitude toward psychiatric medications. Extrapyramidal symptoms did not predict drug attitude. Drug attitudes were no different between patients taking first- or second-generation antipsychotics or clozapine.. Patients may not favor second-generation over first-generation antipsychotics, and extrapyramidal symptoms may not be a primary factor determining attitudes. While attitudes may be more positive in patients who recognize therapeutic drug effects, patients who work may view medications particularly negatively, possibly due to a sense of stigma. Because drug attitudes may reflect compliance and are difficult to predict, clinicians should inquire directly.

    Topics: Adult; Aged; Ambulatory Care; Antipsychotic Agents; Attitude to Health; Awareness; Basal Ganglia Diseases; Clozapine; Cross-Sectional Studies; Diagnostic and Statistical Manual of Mental Disorders; Employment; Female; Humans; Male; Middle Aged; Patient Compliance; Psychiatric Status Rating Scales; Schizophrenia; Schizophrenic Psychology; Stereotyping

2004
The acute EPS of haloperidol may be unrelated to its metabolic transformation to BCPP+.
    Bioorganic & medicinal chemistry letters, 2003, Nov-03, Volume: 13, Issue:21

    We have previously proposed that haloperidol's debilitating extrapyramidal symptoms (EPS) may be associated with its quaternary BCPP+ (an MPP+ like species) metabolite formed in vivo. However, recent work on D2 knock out mice suggests that haloperidol's EPS may be related to its potent D2 binding (K(i)=0.9 nM). In this study, we explore this question by synthesizing and testing an analogue (DS-27) that binds to D2 receptors with higher affinity than haloperidol, but cannot form quaternary metabolites. This study suggests that D2 affinity may be the primary underlying mechanism for acute catalepsy induction by haloperidol.

    Topics: Acetyl-CoA Carboxylase; Animals; Antipsychotic Agents; Apomorphine; Basal Ganglia Diseases; Carrier Proteins; Catalepsy; Dopamine Agonists; Fatty Acid Synthase, Type II; Haloperidol; Humans; Male; Mice; Psychomotor Performance; Radioligand Assay; Rats; Rats, Sprague-Dawley; Receptors, Dopamine D2; Stereotyped Behavior

2003
Comparative effectiveness of antipsychotic drugs.
    The American journal of psychiatry, 2003, Volume: 160, Issue:3

    Topics: Antipsychotic Agents; Basal Ganglia Diseases; Benzodiazepines; Clinical Trials as Topic; Clozapine; Dose-Response Relationship, Drug; Drug Administration Schedule; Haloperidol; Humans; Olanzapine; Pirenzepine; Psychotic Disorders; Research Design; Risperidone; Schizophrenia; Treatment Outcome

2003
Tobacco and cannabis smoking cessation can lead to intoxication with clozapine or olanzapine.
    International clinical psychopharmacology, 2002, Volume: 17, Issue:3

    Plasma levels of clozapine and olanzapine are lower in smokers than in nonsmokers, which is mainly due to induction of cytochrome P4501A2 (CYP1A2) by some smoke constituents. Smoking cessation in patients treated with antipsychotic drugs that are CYP1A2 substrates may result in increased plasma levels of the drug and, consequently, in adverse drug effects. Two cases of patients who smoked tobacco and cannabis are reported. The first patient, who was receiving clozapine treatment, developed confusion after tobacco and cannabis smoking cessation, which was related to increased clozapine plasma levels. The second patient, who was receiving olanzapine treatment, showed important extrapyramidal motor symptoms after reducing his tobacco consumption. The clinical implication of these observations is that smoking patients treated with CYP1A2 substrate antipsychotics should regularly be monitored with regard to their smoking consumption in order to adjust doses in cases of a reduction or increase in smoking.

    Topics: Adult; Antipsychotic Agents; Basal Ganglia Diseases; Benzodiazepines; Clozapine; Confusion; Cytochrome P-450 CYP1A2; Humans; Male; Marijuana Smoking; Olanzapine; Pirenzepine; Smoking; Smoking Cessation

2002
Increased dopamine d(2) receptor occupancy and elevated prolactin level associated with addition of haloperidol to clozapine.
    The American journal of psychiatry, 2001, Volume: 158, Issue:2

    The authors added haloperidol, a potent D(2) blocker, to ongoing treatment with clozapine in patients with schizophrenia to determine the effects of this combination on dopamine D(2) receptor blockade, prolactin level, and extrapyramidal side effects.. At baseline and 4-8 weeks after the addition of haloperidol (4 mg/day) to ongoing clozapine treatment, five patients were examined for prolactin elevation, extrapyramidal side effects, drug plasma levels, and D(2) receptor occupancy measured with [(11)C]raclopride and positron emission tomography imaging.. Adding haloperidol significantly increased D(2) receptor occupancy, from a mean of 55% to 79%, and significantly increased the prolactin level. One patient developed akathisia, and another manifested mild extrapyramidal side effects.. Adding a modest dose of haloperidol to clozapine results in the high D(2) receptor occupancy and sustained prolactin elevation usually associated with typical antipsychotics. These findings suggest that the lack of prolactin elevation associated with clozapine derives mainly from low D(2) receptor occupancy and not from the medication's effects on other receptors.

    Topics: Adult; Antipsychotic Agents; Basal Ganglia Diseases; Clozapine; Corpus Striatum; Drug Therapy, Combination; Haloperidol; Humans; Male; Prolactin; Raclopride; Receptors, Dopamine D2; Schizophrenia; Tomography, Emission-Computed

2001
Evaluation of the neurotoxic activity of typical and atypical neuroleptics: relevance to iatrogenic extrapyramidal symptoms.
    Cellular and molecular neurobiology, 2001, Volume: 21, Issue:6

    Typical neuroleptic therapy often results in extrapyramidal symptoms (EPS) and tardive dyskinesia (TD). Recent reports reveal neurotoxic activity in some neuroleptics. We hypothesized that neurotoxicity might be implicated in EPS. This study aims to evaluate the neurotoxic activity of typical and atypical neuroleptics and to determine the possible role of neurotoxicity in neuroleptic-induced EPS. Perphenazine, haloperidol, clozapine, sulpiride, and risperidone (10-100 microM) were administered, either alone or combined with dopamine, to primary mouse neuronal or intact brain culture and to a human neuroblastoma (NB) cell line (SK-N-SH). Cell viability (measured by neutral red and alamar blue), DNA fragmentation (flow cytometry-NB) were determined. Neuroblastoma: perphenazine, clozapine, and haloperidol (100 microM) decreased viability by 87, 43, and 34% respectively. Sulpiride and risperidone were not toxic. At 10 microM, toxicity decreased markedly. Dopamine (125 microM) potentiated the perphenazine-induced toxicity. Flow cytometry of NB cells treated with perphenazine (2.5-40 microM) showed an increase (perphenazine 20 microM, 40 microM, 48 h) in fragmented DNA (74.7% and 95.0% vs. 8.7% in controls). Lower concentrations increased the G1 phase and decreased S phase in the cell cycle. In primary neurons, perphenazine, haloperidol, and clozapine, but not risperidone and sulpiride, induced a significant neurotoxic effect, which, in intact brain culture, was absent (haloperidol and clozapine) or lowered (perphenazine). Dopamine (0.5 mM) did not modify the effect of the drugs in the primary cultures. Neuroleptics possess differential neurotoxic activity with higher sensitivity of neoplasm tissue (NB compared to primary cultures). The order of toxicity was perphenazine > haloperidol = clozapine:sulpiride and risperidone were not toxic. Neurotoxicity is independent of dopamine and is associated with cell cycle arrest and apoptosis. With the exception of clozapine, neurotoxicity seems relevant to neuroleptic-induced EPS and TD.

    Topics: Animals; Antipsychotic Agents; Basal Ganglia Diseases; Brain; Cell Cycle; Cell Survival; Clozapine; DNA Fragmentation; Dopamine; Dose-Response Relationship, Drug; Dyskinesia, Drug-Induced; Female; Haloperidol; Humans; Iatrogenic Disease; Mice; Mice, Inbred ICR; Neurons; Neurotoxins; Perphenazine; Pregnancy; Risperidone; Tumor Cells, Cultured

2001
"New" rather than "atypical".
    Psychopharmacology, 2000, Volume: 148, Issue:1

    Topics: Antipsychotic Agents; Basal Ganglia Diseases; Clozapine; Humans; Receptors, Dopamine D2; Receptors, Serotonin; Schizophrenia; Terminology as Topic

2000
Tardive dyskinesia in older patients.
    The Journal of clinical psychiatry, 2000, Volume: 61 Suppl 4

    Neuroleptic-induced tardive dyskinesia, which often appears in middle-aged and older adults early in the course of treatment with low doses of conventional antipsychotics, is 5 to 6 times more prevalent in elderly than in younger patients. In addition to age, other risk factors for tardive dyskinesia include early extrapyramidal symptoms (EPS), cumulative amounts of neuroleptics, duration of neuroleptic treatment, and history of alcohol abuse and/or dependence. The atypical antipsychotics, which have a low liability for EPS, are likely to also have low potential for tardive dyskinesia, despite the paucity of controlled studies. Starting and maintenance doses of the atypical antipsychotics should generally be lower in older than in younger adults.

    Topics: Adult; Age Factors; Aged; Alzheimer Disease; Antipsychotic Agents; Basal Ganglia Diseases; Benzodiazepines; Clinical Trials as Topic; Clozapine; Dibenzothiazepines; Drug Administration Schedule; Dyskinesia, Drug-Induced; Female; Humans; Incidence; Male; Middle Aged; Olanzapine; Pirenzepine; Psychotic Disorders; Quetiapine Fumarate; Risk Factors; Risperidone

2000
Prevalence of extrapyramidal syndromes in psychiatric inpatients and the relationship of clozapine treatment to tardive dyskinesia.
    Schizophrenia research, 2000, May-05, Volume: 42, Issue:3

    In 200 inpatients on regular neuroleptics, point prevalence of extrapyramidal syndromes, including Parkinson syndrome, akathisia and tardive dyskinesia (TD), was studied and found to be 20, 11 and 22%, respectively. A total of 46 patients have currently, and for a longer time, (average about 3years, median over 1year) been treated with clozapine, and 127 with typical neuroleptics (NLs). Comparing both groups, higher TD scores were found in the clozapine sample. Investigating the influence of a set of seven clinical variables on the TD score with the help of multiple regression analysis, the influence of the treatment modality disappeared, whereas the age proved to be the only significant variable. Studying the role of past clozapine therapy in patients currently on typical NLs and comparing 10 matched pairs of chronic patients with and without TD in whom a complete life-time cumulative dose of NLs was identified, a relationship between TD and length of current typical NL therapy and life-time typical NL dosage could be demonstrated. On the whole, long-term relatively extensive use of clozapine has not markedly reduced the prevalence of extrapyramidal syndromes in our psychiatric inpatient population. In particular, we failed to demonstrate a beneficial effect of clozapine on prevalence of TD. There are certainly patients who suffer from TD in spite of a long-term intensive clozapine treatment.

    Topics: Antipsychotic Agents; Basal Ganglia Diseases; Chronic Disease; Clozapine; Dyskinesia, Drug-Induced; Female; Humans; Male; Mental Disorders; Middle Aged; Prevalence; Time Factors

2000
Side Effects of Antipsychotic Medications: Physician's Choice of Medication and Patient Compliance. Dallas, Texas, California. January 22, 1999. Proceedings of a roundtable.
    The Journal of clinical psychiatry, 2000, Volume: 61 Suppl 8

    Topics: Agranulocytosis; Antipsychotic Agents; Basal Ganglia Diseases; Benzodiazepines; Clozapine; Dibenzothiazepines; Humans; Olanzapine; Patient Compliance; Pirenzepine; Practice Patterns, Physicians'; Quality of Life; Quetiapine Fumarate; Risperidone

2000
Side effects of antipsychotics in the elderly.
    The Journal of clinical psychiatry, 2000, Volume: 61 Suppl 8

    Side effects of antipsychotic medications are particularly problematic in elderly patients, who experience many age-related changes that may exacerbate medication side effects. Side effects of particular concern in the elderly include anticholinergic reactions, parkinsonian events, tardive dyskinesia, orthostatic hypotension, cardiac conduction disturbances, reduced bone mineral density, sedation, and cognitive slowing. In addition, elderly patients with schizophrenia often have comorbid medical illnesses-such as cardiovascular disease and dementia of the Alzheimer's type-and are thus likely to be taking multiple medications. The effects of polypharmacy must be carefully considered. Patients, caregivers, and family often have different perspectives on side effects. This article addresses the side effects of the currently available antipsychotic medications in light of these concerns.

    Topics: Age Factors; Aged; Antipsychotic Agents; Basal Ganglia Diseases; Clinical Trials as Topic; Clozapine; Comorbidity; Dementia; Dibenzothiazepines; Humans; Movement Disorders; Neuroleptic Malignant Syndrome; Psychotic Disorders; Quetiapine Fumarate; Risperidone; Schizophrenia

2000
Clozapine-associated extrapyramidal reaction.
    The Annals of pharmacotherapy, 2000, Volume: 34, Issue:5

    To report a case of extrapyramidal reaction associated with a dosage increase of clozapine.. A 44-year-old white man with a 20-year history of chronic paranoid schizophrenia was admitted to an inpatient psychiatric facility. His prior medications restarted on admission were clozapine 650 mg at bedtime, haloperidol 10 mg at bedtime, clonazepam 2 mg/d, and aspirin 325 mg/d. Two days after admission (hospital day 3), clozapine and clonazepam were discontinued, and he was prescribed haloperidol 5 mg every morning and 10 mg every evening. Stabilization occurred over the following 24 days, with progressively lower dosages of haloperidol and increasing dosages of clozapine. Haloperidol was discontinued on day 24. On day 47, the patient was agitated and making bizarre statements; thus, the morning dose of clozapine was increased by 50 mg (total 450 mg/d). On day 48 at 2200, a dystonic reaction was diagnosed; he received intramuscular diphenhydramine 50 mg, which caused the reaction to subside. At the time of the adverse reaction, he was prescribed clozapine 450 mg/d, vitamin E 400 IU three times daily, aspirin 325 mg/d, and acetaminophen, milk of magnesia, and Maalox as needed.. Although the risk of extrapyramidal symptoms (EPS) is significantly lower with clozapine than with conventional agents, elevated clozapine blood concentrations have been reported to cause EPS; other reports have cited severe dystonias and dyskinesias on abrupt clozapine withdrawal. Considering the medications prescribed at the time and the discontinuation of haloperidol 24 days before the event, clozapine was the most likely cause of the extrapyramidal reaction.. Regardless of anticipated safety associated with novel antipsychotics such as clozapine, reports of dystonic reactions must be taken into account and patients monitored appropriately.

    Topics: Adult; Antipsychotic Agents; Basal Ganglia Diseases; Clozapine; Dyskinesias; Dystonia; Humans; Male; Schizophrenia

2000
Combined 5-HT2/D2 receptor blockade inhibits the firing rate of SNR neurons in the rat brain.
    Progress in neuro-psychopharmacology & biological psychiatry, 2000, Volume: 24, Issue:4

    1. The aim of the present study was to evaluate the contribution of serotonin (5-HT) and dopamine (DA) receptor antagonism to the distinct inhibitory effects of the atypical antipsychotics clozapine and risperidone on SNR neurons, we have shown previously. 2. Utilizing extracellular recordings in the SNR in chloral hydrate anaesthetized rats, raclopride, a selective DA D2/D3 receptor antagonist and LY 53857, a 5-HT2A:2c receptor antagonist were studied separately and in combination for their effects on the firing rate of the SNR neurons. 3. Both raclopride and LY 53857 induced a slight but significant increase in the firing rate of the SNR neurons in a limited dose range. 4. Upon pretreatment with a single dose of raclopride, LY 53857 induced a dose-dependent inhibitory effect on the firing rate of the SNR neurons. 5. Concurrent 5-HT2 and moderate DA D2 receptor antagonism can mimic the in vivo effects of the atypical antipsychotics clozapine and risperidone on the firing rate of SNR neurons.

    Topics: Animals; Antipsychotic Agents; Basal Ganglia Diseases; Clozapine; Electrophysiology; Male; Neurons; Rats; Rats, Wistar; Receptors, Dopamine; Receptors, Serotonin; Risperidone; Substantia Nigra

2000
Low-dose clozapine pretreatment partially prevents haloperidol-induced deficits in conditioned active avoidance.
    Behavioural pharmacology, 2000, Volume: 11, Issue:3-4

    The effectiveness of neuroleptics in disrupting conditioned active avoidance has led to the widespread use of this test as an index of antipsychotic efficacy, whereas the tendency for these drugs to induce catalepsy is believed to reflect their propensity to cause extrapyramidal motor side-effects. Although the typical neuroleptic haloperidol produces catalepsy as well as profound deficits in conditioned active avoidance, the atypical neuroleptic clozapine does not induce catalepsy and is less effective than haloperidol in disrupting active avoidance. Furthermore, clozapine pretreatment prevents haloperidol-induced catalepsy. We investigated whether clozapine pretreatment might also reduce the disruptive effects of haloperidol on two-way active avoidance. We assessed the avoidance acquisition of the following drug treatment groups in which all animals received two injections prior to testing: vehicle + vehicle, vehicle + haloperidol (0.1 mg/kg, i.p.), clozapine (2.5, 5.0 or 10 mg/kg, i.p.) + haloperidol (0.1 mg/kg, i.p.), or clozapine (2.5, 5.0 or 10 mg/kg, i.p.) + vehicle. Haloperidol-pretreated animals showed markedly impaired active avoidance, deficits which were improved by 2.5 and 5 mg/kg but not by 10 mg/kg clozapine pretreatment. These data suggest that the disruptive effects of haloperidol on conditioned active avoidance partially mirror its capacity to induce catalepsy and extrapyramidal motor symptoms. Furthermore, this study indicates that clozapine may be effective in reducing motor side-effects caused by typical neuroleptics.

    Topics: Animals; Antipsychotic Agents; Avoidance Learning; Basal Ganglia Diseases; Catalepsy; Clozapine; Conditioning, Classical; Drug Interactions; Haloperidol; Male; Rats; Rats, Wistar

2000
Atypical antipsychotic effects of quetiapine fumarate in animal models.
    Acta pharmacologica Sinica, 2000, Volume: 21, Issue:3

    To evaluate the effect of quetiapine fumarate in animal models of schizophrenia and its possibility to induce extrapyramidal side effects (EPSE).. The enhancement of immobility in a forced swimming test of mice induced by repeated treatment with phencyclidine and amphetamine swimming "normalization" test of mice were used as animal models of negative and positive symptoms of schizophrenia, respectively. The paw test of rats was used to evaluate the possibility by quetiapine fumarate to induce EPSE.. After treatment with phencyclidine (10 mg.kg-1.d-1, s.c., 14 d), the immobility time in the forced swimming test of mice was increased (P < 0.01). Quetiapine fumarate (20, 40, and 80 mg.kg-1, ig) and clozapine (10 and 30 mg.kg-1, ig) attenuated the enhanced immobility in the forced swimming test induced by repeated treatment with phencyclidine (P < 0.01), whereas haloperidol (0.3 and 1 mg.kg-1, ig) had no effect. In amphetamine swimming "normalization" test, quetiapine fumarate ameliorated the disorder induced by amphetamine in a dose-dependent manner. In paw test, quetiapine fumarate was much less effective in increasing the forelimb retraction time (FRT) than the hindlimb retraction time (HRT). The minimal effective dose (MED) of HRT (MEDHRT) and FRT (MEDFRT) of quetiapine fumarate was 20 mg.kg-1 and 100 mg.kg-1, respectively, and the ratio of MEDFRT to MEDHRT was 5.. The effects of quetiapine fumarate in these models indicated its clinical effect on schizophrenia with a reduced liability to produce EPSE.

    Topics: Amphetamine; Animals; Antipsychotic Agents; Basal Ganglia Diseases; Clozapine; Disease Models, Animal; Female; Haloperidol; Immobilization; Male; Mice; Phencyclidine; Rats; Rats, Wistar; Schizophrenia; Schizophrenia, Paranoid

2000
Effects of acute and chronic administration of olanzapine in comparison to clozapine and haloperidol on extracellular recordings of substantia nigra reticulata neurons in the rat brain.
    Psychopharmacology, 1999, Volume: 144, Issue:3

    Previously, we have shown that the atypical antipsychotics clozapine and risperidone, unlike haloperidol, decreased the firing rate of substantia nigra reticulata (SNR) neurons. As the SNR receives substantial input from the striatum, an area where motoric side-effects of antipsychotics are thought to be mediated, the SNR might be an interesting brain structure with regard to motor side-effects.. The newly developed atypical antipsychotic olanzapine was studied for its effects on the firing rate of SNR cells. In addition, to gain insight in the implications of our experimental setup for clinical use, responses upon clozapine, olanzapine and haloperidol were studied after chronic treatment.. In chloralhydrate-anaesthetized male Wistar rats, extracellular recordings were made from SNR neurons upon intravenously (i.v.) administered cumulative doses of the antipsychotics. Naive rats and rats that were subcutaneously (SC) injected for 21 days with an antipsychotic were used.. Olanzapine (50-1600 mg/kg; i.v.), significantly inhibited the firing rate of the SNR neurons. Upon 21 days of treatment with a daily SC injection of 20 mg/kg clozapine, the challenge on day 22 with cumulative injections of clozapine (200 6400 mg/kg; i.v.) significantly inhibited the firing rate of the SNR neurons. Olanzapine (50-1600 mg/kg; i.v.) also significantly inhibited the SNR activity when pretreated with olanzapine in an SC administered dose of 1 mg/kg, but not 5 mg/kg. Haloperidol (12.5-800 microg/kg; i.v.) did not significantly affect the SNR activity in rats pretreated with SC administered 0.5 mg/kg haloperidol.. Upon acute and chronic administration of clozapine and olanzapine versus haloperidol, differential effects on SNR neuronal firing could be obtained. The experimental setup seem to be valid for further studies into the mechanism of action of typical versus (relatively low doses of) atypical antipsychotics. The implications of the inhibitory effect of atypical antipsychotics on the SNR firing rate are presently unknown, but could be associated with the lower propensity to induced motoric side-effects. On the other hand, the SNR activity might also reflect non-motoric activity possibly related to negative symptoms.

    Topics: Animals; Antipsychotic Agents; Basal Ganglia Diseases; Benzodiazepines; Clozapine; Haloperidol; Male; Neurons; Olanzapine; Pirenzepine; Rats; Rats, Wistar; Substantia Nigra

1999
Deterioration of parkinsonian symptoms following treatment of dopaminergic hallucinosis with olanzapine.
    European psychiatry : the journal of the Association of European Psychiatrists, 1999, Volume: 14, Issue:6

    The atypical antipsychotic drug olanzapine has been proposed for treatment of dopaminergic psychosis in Parkinson's disease (PD). We report on a 68-year-old patient who developed a severe akinetic-rigid extrapyramidal syndrome, accompanied by additional paranoid symptoms, following olanzapine treatment of optic hallucinosis in PD. Olanzapine may also induce clinically relevant extrapyramidal side effects in PD patients.

    Topics: Aged; Antiparkinson Agents; Antipsychotic Agents; Basal Ganglia Diseases; Benzodiazepines; Clozapine; Drug Therapy, Combination; Hallucinations; Humans; Levodopa; Male; Olanzapine; Paranoid Disorders; Parkinson Disease; Piperidines; Pirenzepine; Selegiline; Severity of Illness Index

1999
Effects of subchronic administration of clozapine, thioridazine and haloperidol on tests related to extrapyramidal motor function in the rat.
    Psychopharmacology, 1998, Volume: 137, Issue:1

    Clozapine, thioridazine (THIO) and haloperidol were administered for 14 consecutive days, and separate groups of rats were used to study the effects of these drugs on tremulous jaw movements and lever pressing. Rats were observed on day 13 for the ability of the antipsychotic drugs to induce jaw movements. Haloperidol produced a dose-related increase in jaw movements, while clozapine and THIO failed to induce jaw movements. On day 14, rats were challenged with 5.0 mg/kg of the anticholinesterase tacrine, which induces a very high level of jaw movement activity. Clozapine significantly reduced tacrine-induced tremulous jaw movements, while haloperidol did not. Although previous work had shown that acute THIO could suppress jaw movements, repeated THIO failed to do so. In order to provide an additional behavioral test for comparisons of the relative potencies of the antipsychotic drugs, rats were tested for the effects of these drugs on fixed ratio 5 lever pressing. All three drugs significantly suppressed lever pressing. Haloperidol showed sensitization with repeated injections, while clozapine showed tolerance. Data were analyzed by taking the ratio of the ED50 for suppression of tacrine-induced jaw movement over the ED50 for suppression of lever pressing on day 14. Clozapine reduced tacrine-induced jaw movements in a dose range slightly lower than that required for reduction of lever pressing. In contrast, THIO and haloperidol failed to affect tacrine-induced jaw movements even at doses that were 5-18 times the ED50 for suppression of lever pressing. Thus, tests of jaw movement activity and lever pressing after repeated administration may be useful for assessing atypical antipsychotic drugs.

    Topics: Animals; Antipsychotic Agents; Basal Ganglia Diseases; Clozapine; Conditioning, Operant; Haloperidol; Jaw; Male; Movement; Rats; Rats, Sprague-Dawley; Tacrine; Thioridazine

1998
Iodine-123-iodobenzamide SPECT assessment of dopamine D2 receptor occupancy in riperidone-treated schizophrenic patients.
    Journal of nuclear medicine : official publication, Society of Nuclear Medicine, 1998, Volume: 39, Issue:7

    The recently introduced neuroleptic, risperidone, was expected to block fewer dopamine D2 receptors than typical neuroleptics (e.g., haloperidol), but at comparable potency. The aim of this study was to evaluate the degree of dopamine D2 receptor occupancy in relation to the neuroleptic dosage and to correlate the findings with the presence of extrapyramidal symptoms (EPS). Additionally, the data were compared to previous iodobenzamide (IBZM) SPECT findings in patients treated with other neuroleptics, haloperidol and clozapine.. In 20 patients with schizophrenia [Diagnostic and Statistical Manual of Mental Disorders (Third Edition-Revised)] treated with mean daily doses of risperidone ranging from 0.029 to 0.128 mg/kg body weight, SPECT was performed 2 hr after intravenous injection of 185 MBq 123I-IBZM, a selective dopamine D2 receptor ligand. Striatal IBZM binding was assessed by calculating a striatal/frontal cortex ratio, expressed as a percentage of the control value.. Selective dopamine D2 receptor binding of the ligand was reduced in all treated patients, with binding values ranging from 7% to 68%. The degree of occupancy displayed an exponential dose-response relationship (r = -0.86; p < 0.0001). The slope of the curve was between those of haloperidol and clozapine but was closer and more similar in shape to the curve of haloperidol. Extrapyramidal symptoms were observed in 8 of 20 patients with binding values between 7% and 47%. However, there was no clear relationship between the degree of receptor occupancy and the presence of EPS.. The findings suggest an exponential dose-response relationship between the daily dosage of risperidone and the dopamine D2 receptor occupancy. The blockade of specific striatal IBZM binding found under therapy with risperidone is between those of haloperidol and clozapine. The dose-response curve for risperidone, however, shows greater similarity to that of haloperidol.

    Topics: Adult; Antipsychotic Agents; Basal Ganglia Diseases; Benzamides; Brain; Clozapine; Contrast Media; Dose-Response Relationship, Drug; Female; Haloperidol; Humans; Iodine Radioisotopes; Male; Middle Aged; Pyrrolidines; Receptors, Dopamine D2; Risperidone; Schizophrenia; Tomography, Emission-Computed, Single-Photon

1998
Extrapyramidal symptoms after addition of fluvoxamine to clozapine.
    Journal of clinical psychopharmacology, 1998, Volume: 18, Issue:6

    Topics: Antidepressive Agents, Second-Generation; Antipsychotic Agents; Basal Ganglia Diseases; Clozapine; Drug Interactions; Female; Fluvoxamine; Humans; Male; Middle Aged; Schizophrenia

1998
Involvement of 5-HT6 receptors in nigro-striatal function in rodents.
    British journal of pharmacology, 1998, Volume: 125, Issue:7

    4-Amino-N-(2,4 bis-methylamino-pyrimidin-4-yl) benzene sulphonamide (Ro 04-6790) is a potent, selective and competitive antagonist for the 5-HT6 receptor which can be detected in the cerebro-spinal fluid (CSF) of rats following intraperitoneal administration. Since 5-HT6 receptor mRNA and 5-HT6 receptor-like immunoreactivity have been shown to be present in the striatum, the purpose of the present study was to evaluate the effect of 5-HT6 receptor antagonism on haloperidol- and SCH 23390-induced catalepsy in mice and on the turning behaviour of rats with unilateral 6-hydroxydopamine (6-OHDA) lesions of the medial forebrain bundle. Ro 04-6790 (3, 10 and 30 mg kg(-1) i.p.) did not induce catalepsy and had no effect on catalepsy induced by either haloperidol or SCH 23390. Ro 04-6790 (3, 10 and 30 mg kg(-1) i.p.) did not itself induce rotational behaviour in rats with unilateral 6-hydroxydopamine (6-OHDA) lesions of the medial forebrain bundle nor did it affect the rotational behaviour induced by either L-Dopa or amphetamine. 5-HT6 receptor antagonism inhibited the rotational behaviour of 6-OHDA lesioned rats induced by treatment with the muscarinic antagonists scopolamine and atropine. The data support earlier conclusions from experiments with antisense oligonucleotides that the 5-HT6 receptor is involved in the control of acetylcholine neurotransmission in the rat brain.

    Topics: Adrenergic Agents; Animals; Basal Ganglia Diseases; Benzazepines; Catalepsy; Clozapine; Corpus Striatum; Haloperidol; Male; Mice; Oxidopamine; Prosencephalon; Pyrimidines; Rats; Receptors, Serotonin; Serotonin Antagonists

1998
5-HT2A receptor blockade in patients with schizophrenia treated with risperidone or clozapine. A SPET study using the novel 5-HT2A ligand 123I-5-I-R-91150.
    The British journal of psychiatry : the journal of mental science, 1998, Volume: 173

    5-HT2A receptor antagonism may be crucial to the action of atypical antipsychotics. Previous work has related 5-HT2A receptor blockade to clinical efficacy and protection from extrapyramidal side-effects.. We developed a SPET imaging protocol for assessing 5-HT2A receptor binding using the selective ligand 123I-5-I-R91150. Six healthy volunteers, five clozapine- and five risperidone-treated subjects with DSM-IV schizophrenia were studied. Multi-slice SPET was performed on each subject.. Cortex:cerebellum ratios were significantly lower in both clozapine- and risperidone-treated subjects compared with the healthy volunteers in all cortical regions. There was no difference in occupancy between the two drug-treated groups. No correlation was found between the percentage change in the Global Assessment Scale (GAS) and 5-HT2A receptor binding indices in the drug-treated groups.. Clozapine and risperidone potently block 5-HT2A receptors in vivo. The lack of relationship between receptor binding indices and change in GAS suggests that 5-HT2A receptor blockade may be unrelated to clinical improvement. Future studies will substantiate this finding by studying 5-HT2A receptor binding in large groups of patients treated with both typical and novel atypical antipsychotics.

    Topics: Adult; Basal Ganglia Diseases; Clozapine; Female; Humans; Iodine Radioisotopes; Male; Piperidines; Receptors, Serotonin; Risperidone; Schizophrenia; Serotonin Antagonists; Tomography, Emission-Computed, Single-Photon

1998
Conventional versus atypical neuroleptics: subjective quality of life in schizophrenic patients.
    The British journal of psychiatry : the journal of mental science, 1997, Volume: 170

    The effectiveness of antipsychotic drugs against positive psychotic symptoms has been demonstrated in many studies, but their effects on quality of life have yet to be clarified. The impact of different neuroleptic therapies on the subjective quality of life of schizophrenic patients is evaluated in a cross-sectional open study.. During a four-month period a standardised quality of life interview for schizophrenic patients was applied on day 10 after admission; 33 patients on atypical neuroleptics (AAP) were compared with 31 matched patients on conventional neuroleptics (CAP).. The AAP group had significantly higher scores in general quality of life as well as in different life domains: physical well-being, social life and everyday life. In separate comparisons of the AAP group, patients on clozapine and risperidone were found to have a higher quality of life score than patients on CAP or zotepine.. The pharmacological profile of clozapine and risperidone may provide a basis for explaining the higher subjective quality of life found in this study. The lower quality of life of the CAP group may possibly be related to intrinsic effects of the conventional antipsychotics.

    Topics: Adult; Analysis of Variance; Antipsychotic Agents; Basal Ganglia Diseases; Clozapine; Cross-Sectional Studies; Depression; Dibenzothiepins; Female; Humans; Male; Middle Aged; Quality of Life; Risperidone; Schizophrenia; Schizophrenic Psychology

1997
[123I]IBZM SPECT in patients treated with typical and atypical neuroleptics: relationship to drug plasma levels and extrapyramidal side effects.
    Psychiatry research, 1997, Sep-29, Volume: 75, Issue:2

    [123I]Iodobenzamide (IBZM) is an iodine-labeled dopamine receptor ligand and can be used to visualize brain D2 receptors in humans with single photon emission computerized tomography (SPECT). The ratio of striatal IBZM uptake to uptake in frontal cortex (ST/FC ratio) represents a semiquantitative measure of D2 receptor binding in the striatum. Our study sample included six patients treated with haloperidol (3.0-8.0 mg/day orally; one patient with an average of 0.9 mg/day intramuscularly), five patients with benperidol (9.0-15.0 mg/day orally) and nine patients treated with clozapine (200.0-600.0 mg/day orally). Typical neuroleptics (TNs) and atypical neuroleptics (ANs) were significantly different in their ST/FC ratios. The ST/FC ratios indicated that patients treated with benperidol exhibited the lowest ST/FC ratios, with increasingly higher ratios in patients on haloperidol or clozapine. We found a curvilinear relationship between the ST/FC ratios and the dose/kg body wt. of TNs and ANs on the basis of a dose-normalization according to Ki-values of the neuroleptic at D2 receptors and a weaker, but also curvilinear relationship between ST/FC ratios and normalized dosages according to clinically defined chlorpromazine equivalents. The specific uptake of IBZM did not correlate with the plasma levels of the TN haloperidol at the present dose range (0-12.4 ng/ml). For clozapine, a meaningful negative correlation between plasma levels and ST/FC ratio could be established. There was a negative continuous correlation between uptake of IBZM and extrapyramidal side effects, which is different from the threshold-based relationship between extrapyramidal side effects and IBZM uptake reported previously.

    Topics: Adult; Aged; Antipsychotic Agents; Basal Ganglia Diseases; Benperidol; Benzamides; Bipolar Disorder; Brain; Clozapine; Corpus Striatum; Depressive Disorder, Major; Dopamine Antagonists; Dose-Response Relationship, Drug; Female; Frontal Lobe; Haloperidol; Humans; Male; Middle Aged; Neurologic Examination; Psychiatric Status Rating Scales; Pyrrolidines; Receptors, Dopamine D2; Schizophrenia, Paranoid; Tomography, Emission-Computed, Single-Photon

1997
Iloperidone binding to human and rat dopamine and 5-HT receptors.
    European journal of pharmacology, 1996, Dec-19, Volume: 317, Issue:2-3

    Iloperidone (HP 873; 1-[4-[3-[4-(6-fluoro-1,2-benzisoxazol-3-yl)-1-piperidinyl]propoxy] -3- methoxyphenyl]ethanone) is a compound currently in clinical trials for the treatment of schizophrenia. Iloperidone displays affinity for dopamine D2 receptors and for 5-HT2A receptors and has a variety of in vivo activities suggestive of an atypical antipsychotic. Here we present an examination of the affinity of iloperidone to a variety of human and rat homologs of dopamine and 5-HT receptor subtypes. We employed receptor binding assays using membranes from cells stably expressing human dopamine D1, D2S, D2L, D3, D4 and D5 and 5-HT2A and 5-HT2C receptors and rat 5-HT6 and 5-HT7 receptors. Iloperidone displayed higher affinity for the dopamine D3 receptor (Ki = 7.1 nM) than for the dopamine D4 receptor (Ki = 25 nM). Iloperidone displayed high affinity for the 5-HT6 and 5-HT7 receptors (Ki = 42.7 and 21.6 nM, respectively), and was found to have higher affinity for the 5-HT2A (Ki = 5.6 nM) than for the 5-HT2C receptor (Ki = 42.8 nM). The potential implications of this receptor binding profile are discussed in comparison with data for other antipsychotic compounds.

    Topics: Animals; Antipsychotic Agents; Basal Ganglia Diseases; CHO Cells; Cricetinae; Humans; Isoxazoles; Kinetics; Piperidines; Rats; Receptors, Dopamine; Receptors, Dopamine D1; Receptors, Dopamine D2; Receptors, Dopamine D3; Receptors, Dopamine D4; Receptors, Dopamine D5; Receptors, Serotonin

1996
Choosing among old and new antipsychotics.
    The Journal of clinical psychiatry, 1996, Volume: 57, Issue:9

    Topics: Antipsychotic Agents; Basal Ganglia Diseases; Clozapine; Humans; Psychotic Disorders; Receptors, Dopamine; Receptors, Neurotransmitter; Risk Factors; Risperidone; Schizophrenia

1996
The pharmacological profile of iloperidone, a novel atypical antipsychotic agent.
    The Journal of pharmacology and experimental therapeutics, 1995, Volume: 274, Issue:3

    Iloperidone (1-[4-[3-[4-(6-fluoro-1,2-benzisoxazol-3-yl)-1- piperidinyl]propoxy]-3-methoxyphenyl]ethanone) demonstrated a potent antipsychotic profile in several in vitro and in vivo animal models. Iloperidone displaced ligand binding at D2 dopamine receptors (IC50 = 0.11 microM) and displayed a high affinity for serotonin (5-HT2) receptors (IC50 = 0.011 microM) and alpha-1 receptors (IC50 = 0.00037 microM). In vivo, iloperidone antagonized apomorphine-induced climbing behavior in mice at low doses with good oral bioavailability, prevented 5-HT-induced head twitch in rats at low doses, and inhibited self-stimulation behavior in rats, pole climb avoidance in rats and continuous Sidman avoidance responding in monkeys. The latter assay also demonstrated a good duration of action. Iloperidone was substantially less active in models of extrapyramidal side effect (EPS) liability, such as preventing apomorphine-induced stereotypy and causing catalepsy in rats. In single dopamine neuron sampling studies, iloperidone demonstrated clozapine-like effects on the number of active midbrain dopamine neurons. Based on the significant increase in the open arm time seen after iloperidone treatment in the elevated plus maze assay and increased interaction score in social interaction, iloperidone may also have favorable effects in the clinic on anxiety and, possibly, negative symptoms. Clinical trials are under way of the use of iloperidone for the treatment of schizophrenia.

    Topics: Animals; Anti-Anxiety Agents; Antipsychotic Agents; Basal Ganglia Diseases; Behavior, Animal; Clozapine; Dopamine Antagonists; Haloperidol; Isoxazoles; Male; Mice; Piperidines; Radioligand Assay; Rats; Rats, Wistar; Risperidone; Saimiri; Serotonin Antagonists

1995
D2-dopamine receptor occupancy differs between patients with and without extrapyramidal side effects.
    Acta psychiatrica Scandinavica, 1994, Volume: 90, Issue:4

    To investigate whether the occurrence of extrapyramidal side effects was related to D2 dopamine receptor occupancy, iodobenzamide single positron emission computed tomography was carried out in 27 schizophrenic patients and 10 controls. Eighteen patients were treated with haloperidol; 9 patients were treated with clozapine. Our data suggest a relationship between D2 receptor occupancy and extrapyramidal side effects as well as the existence of a neuroleptic threshold of a striatal:frontal cortex ratio of 1.2, below which drug-induced exptrapyramidal side effects can be expected.

    Topics: Adult; Basal Ganglia Diseases; Clozapine; Dose-Response Relationship, Drug; Dyskinesia, Drug-Induced; Extrapyramidal Tracts; Female; Haloperidol; Humans; Male; Middle Aged; Neurologic Examination; Receptors, Dopamine D2; Schizophrenia; Schizophrenic Psychology; Tomography, Emission-Computed, Single-Photon

1994
The role of serotonin receptor subtypes in the behavioural effects of neuroleptic drugs. A paw test study in rats.
    The European journal of neuroscience, 1994, Jan-01, Volume: 6, Issue:1

    The present study was designed to evaluate the roles of serotonin 5-HT1A and 5-HT2 receptors in the effects of neuroleptic drugs in the paw test. This behavioural test has been shown to model both the antipsychotic efficacy as well as the extrapyramidal side-effect liability of neuroleptic drugs. Whereas the 5-HT1A receptor agonist 8-hydroxy-2-(di-n-propylamino)tetralin (8-OHDPAT) reduced the effects of the classical neuroleptic haloperidol, it increased the effects of the atypical neuroleptic clozapine. The 5-HT2 receptor antagonist ketanserin as well as the 5-HT1C/5-HT2 receptor antagonist ritanserin, on the other hand reduced the effects of haloperidol, whereas the 5-HT1C/5-HT2 receptor agonist 1-(2,5-dimethoxy-4-iodophenyl)-2-aminopropane (DOI) reduced the effects of clozapine. The most important finding, however, was that the behavioural effects of different (putative) neuroleptics (fluphenazine, SCH-39166, remoxipride, prothipendyl, thioridazine and risperidone) were differentially influenced by both 8-OHDPAT and DOI, suggesting that there are important differences between the neuronal mechanisms underlying the behavioural effects of these neuroleptic drugs, even within the subclasses of classical and atypical neuroleptics.

    Topics: 8-Hydroxy-2-(di-n-propylamino)tetralin; Amphetamines; Animals; Antipsychotic Agents; Basal Ganglia Diseases; Behavior, Animal; Clozapine; Haloperidol; Ketanserin; Male; Rats; Rats, Wistar; Receptors, Serotonin; Ritanserin; Serotonin Antagonists; Serotonin Receptor Agonists

1994
Peripheral and central adrenoceptor modulation of the behavioural effects of clozapine in the paw test.
    British journal of pharmacology, 1994, Volume: 112, Issue:3

    1. In rats, the atypical neuroleptic, clozapine, has been found to increase the hindlimb retraction time but not the forelimb retraction time, in the paw test. These parameters have predictive validity for the antipsychotic efficacy and extrapyramidal side-effects of drugs, respectively. The present study analysed to what extent drugs acting on adrenoceptors affect the behavioural effect of clozapine in the paw test. 2. The alpha 1-adrenoceptor agonist, ST 587 but not the peripherally working alpha 1-agonist, methoxamine, decreased the effect of clozapine on the hindlimb retraction time. The alpha 1-antagonist phenoxybenzamine increased this effect of clozapine, and blocked the effect of ST 587 on clozapine at low doses. Only the combination of phenoxybenzamine with clozapine produced an increase in forelimb retraction time. 3. The alpha 2-adrenoceptor agonist, clonidine, decreased the effect of clozapine on the hindlimb retraction time. This effect was neither antagonized by the alpha 2-antagonist rauwolscine nor by the alpha 1-antagonist phenoxybenzamine. Rauwolscine or the peripherally working alpha 2-antagonist L-659,066 did not influence the effect of clozapine on the hindlimb retraction time. The forelimb retraction time was not affected by any of the drug combinations. 4. In contrast to the beta 2-adrenoceptor agonist, clenbuterol, which was ineffective, the peripherally acting beta-agonist, (-)-isoprenaline, increased the effects of clozapine on the hindlimb retraction time. The beta-antagonist, (-)-propranolol as well as the peripherally acting beta-antagonist, nadolol decreased this effect of clozapine. Low doses of the peripherally acting beta 1-antagonist, atenolol, as well as low doses of the beta2-antagonist, ICI-118,551, decreased the effect of clozapine. A low dose of nadolol blocked the effect of (-)-isoprenaline on clozapine. Only the combination of clenbuterol with clozapine produced an increase in forelimb retraction time.5. It is concluded that blockade of central alpha l-adrenoceptors plays an important role in the effect of clozapine on the hindlimb retraction time. Furthermore, the effect of clozapine on the hindlimb retraction time is strongly modulated by peripheral beta 1- and/or beta 2-adrenoceptors. Given the predictive validity of the paw test, the presented data suggest that the alpha 1-adrenoceptor antagonist properties of clozapine are important for its therapeutic effects, but not for its lack of extrapyramidal side-effec

    Topics: Adrenergic alpha-1 Receptor Agonists; Adrenergic alpha-1 Receptor Antagonists; Adrenergic alpha-2 Receptor Agonists; Adrenergic alpha-2 Receptor Antagonists; Adrenergic beta-Antagonists; Animals; Antipsychotic Agents; Basal Ganglia Diseases; Behavior, Animal; Central Nervous System; Clozapine; Disease Models, Animal; Drug Interactions; Male; Peripheral Nervous System; Rats; Rats, Wistar; Receptors, Adrenergic

1994
Motor and mental side effects of clozapine.
    The Journal of clinical psychiatry, 1994, Volume: 55 Suppl B

    Long-term experience with clozapine has shown that the agent has a motor and mental side effect profile that is distinct in many ways from classical neuroleptics. It can produce a parkinsonian-like bradykinesia and mild akathisia, but no rigidity and rarely tremor. In patients with tardive dyskinesia induced by other neuroleptics, clozapine permits the dyskinesia to disappear in about half the cases. That clozapine may induce tardive dyskinesia in extremely rare cases cannot be excluded, but it seems more likely that this tardive dyskinesia in clozapine-treated patients is due to previous treatment with classical neuroleptics. The earlier clozapine is started, the less chance for development of tardive dyskinesia. As do other neuroleptics, clozapine can elicit sedation and asthenia, but corresponding to the motoric extrapyramidal syndrome, clozapine causes emotional indifference ("mental parkinsonism"), depression, and restlessness to a significantly lesser degree, which may be of importance in the higher compliance seen with this drug.

    Topics: Affective Symptoms; Akathisia, Drug-Induced; Antipsychotic Agents; Asthenia; Basal Ganglia Diseases; Clozapine; Dyskinesia, Drug-Induced; Dystonia; Humans; Parkinson Disease, Secondary; Schizophrenia; Schizophrenic Psychology

1994
Predictors of response to clozapine.
    The Journal of clinical psychiatry, 1994, Volume: 55 Suppl B

    Clinical and biological measures were examined for their relationship to clinical response to clozapine. Associations were found between therapeutic response and the following variables: male gender, paranoid schizophrenia subtype diagnosis, older age at onset of illness, shorter duration of illness, higher levels of pretreatment acute EPS, low pretreatment CSF HVA/5-HIAA, greater decrease in prolactin (PRL) and increase in growth hormone (GH) response to apomorphine stimulation pretreatment and greater inhibition by clozapine treatment of PRL and GH response to apomorphine, and plasma clozapine levels above 350 ng/mL. These results are consistent with other investigators' findings and have practical and heuristic implications for the use of clozapine and understanding its mechanism of action.

    Topics: Adult; Age Factors; Age of Onset; Antipsychotic Agents; Apomorphine; Basal Ganglia Diseases; Clozapine; Female; Growth Hormone; Humans; Male; Probability; Prolactin; Schizophrenia; Schizophrenic Psychology; Sex Factors; Treatment Outcome

1994
Clozapine, negative symptoms, and extrapyramidal side effects.
    The Journal of clinical psychiatry, 1994, Volume: 55 Suppl B

    The importance of persistent negative symptoms in schizophrenia as a limiting factor in psychosocial and vocational rehabilitation has been increasingly emphasized. As a result, treatment trials and new drug development programs are focusing more attention on negative symptoms. Unfortunately, there is enormous phenomenological overlap between negative symptoms and neuroleptic-induced parkinsonism. We report data from a cohort of 56 clozapine-treated patients demonstrating significant correlations between measures of akinesia and anergia. Despite an average drug washout of over 2 weeks, the persistence of drug-induced parkinsonism can confound the assessment of therapeutic drug effects on negative symptoms.

    Topics: Adolescent; Adult; Basal Ganglia Diseases; Clozapine; Female; Humans; Male; Parkinson Disease, Secondary; Psychiatric Status Rating Scales; Psychotic Disorders; Schizophrenia; Schizophrenic Psychology

1994
Clinical effects of clozapine in chronic schizophrenia: response to treatment and predictors of outcome.
    The American journal of psychiatry, 1994, Volume: 151, Issue:12

    This study addressed the unique clinical properties attributed to the atypical antipsychotic clozapine, including its efficacy in patients with treatment-refractory psychosis and against negative symptoms, its lack of acute extrapyramidal side effects, and the longer time course of its therapeutic effects.. The clinical responses of 84 schizophrenic inpatients (66 with treatment-refractory illness and 18 who were intolerant of antipsychotic treatment) were examined. After all previous antipsychotic medications had been withdrawn, the patients were treated with clozapine according to a standardized titration and dosage schedule. Patients who tolerated and responded to treatment were discharged and maintained on a regimen of clozapine for up to 52 weeks. Patients were evaluated for behavioral response and side effects after weeks 3, 6, 12, 26, 39, and 52 of treatment.. Fifty percent of the patients with treatment-refractory illness and 76% of the treatment-intolerant patients responded to clozapine in up to 52 weeks. The optimal period for a trial of clozapine appeared to be 12-24 weeks. Clozapine exhibited therapeutic effects on negative symptoms, but these were not clearly independent of its effects on positive symptoms and extrapyramidal side effects. Several variables, including early age at onset of illness and female gender, were found to be predictors of poor response to treatment. Predictors of good response included the presence of extrapyramidal side effects during previous treatment with classic neuroleptics and a diagnosis of paranoid schizophrenia.. These findings have important implications for the use of clozapine and our understanding of the pathophysiology of treatment-resistant schizophrenia.

    Topics: Adolescent; Adult; Age of Onset; Antipsychotic Agents; Basal Ganglia Diseases; Chronic Disease; Clozapine; Female; Humans; Male; Probability; Psychiatric Status Rating Scales; Schizophrenia; Schizophrenic Psychology; Sex Factors; Treatment Outcome

1994
Tardive oculogyric crises with clozapine.
    The Journal of clinical psychiatry, 1994, Volume: 55, Issue:6

    Topics: Adult; Basal Ganglia Diseases; Benztropine; Clozapine; Dyskinesia, Drug-Induced; Female; Humans; Ocular Motility Disorders; Schizophrenia, Paranoid

1994
[Pisa syndrome in clozapine therapy].
    Der Nervenarzt, 1993, Volume: 64, Issue:11

    Neuroleptic therapy frequently induces undesirable extrapyramidal side effects. The Pisa syndrome is a rare extrapyramidal side effect caused by neuroleptic treatment. Twisting and bending to one side of the upper thorax, the neck and the head are its typical symptoms. These symptoms mainly develop in elderly patients with a history of neuroleptic treatment. To our knowledge there have been no reports of Pisa syndrome occurring during therapy with clozapine--an atypical neuroleptic drug with no major extrapyramidal side effects. We report on 4 female patients suffering from a chronic schizophrenic and/or depressive condition and having been on a long-term neuroleptic treatment. These patients developed a dystonia equivalent to the Pisa syndrome during an acute clozapine therapy. All four women had signs of marked brain atrophy, two of them also showing tardive dyskinesia already prior to the treatment with clozapine. The etiology of the Pisa syndrome is discussed with respect to discontinuation of treatment with classic neuroleptics, coinciding with the beginning of the clozapine therapy, clinical phenomenology, history of medication, course of treatment, and results of cranial computer tomography.

    Topics: Adult; Affective Disorders, Psychotic; Aged; Basal Ganglia Diseases; Clozapine; Depressive Disorder; Drug Therapy, Combination; Female; Humans; Long-Term Care; Middle Aged; Neurologic Examination; Schizophrenia, Paranoid

1993
Positron emission tomographic analysis of central D1 and D2 dopamine receptor occupancy in patients treated with classical neuroleptics and clozapine. Relation to extrapyramidal side effects.
    Archives of general psychiatry, 1992, Volume: 49, Issue:7

    Positron emission tomography and selective radioligands were used to determine D1 and D2 dopamine receptor occupancy induced by neuroleptics in the basal ganglia of drug-treated schizophrenic patients. In 22 patients treated with conventional dosages of classical neuroleptics, the D2 occupancy was 70% to 89%. Patients with acute extrapyramidal syndromes had a higher D2 occupancy than those without side effects. This finding indicates that neuroleptic-induced extrapyramidal syndromes are related to the degree of central D2 occupancy induced in the basal ganglia. In five patients treated with clozapine, the prototype atypical antipsychotic drug, a lower D2 occupancy of 38% to 63% was found. This finding demonstrates that clozapine is also "atypical" with respect to the central D2 occupancy in patients. During treatment with clozapine, there is a low frequency of extrapyramidal syndromes, which accordingly may reflect the comparatively low D2 occupancy induced by clinical doses of clozapine. Classical neuroleptics, like haloperidol or sulpiride, did not cause any evident D1 occupancy, but the thioxanthene flupentixol induced a 36% to 44% occupancy. In four patients treated with clozapine, the D1 occupancy was 38% to 52%. The D1 occupancy induced by clozapine and flupentixol may contribute to the antipsychotic effect of these drugs.

    Topics: Adolescent; Adult; Antipsychotic Agents; Basal Ganglia; Basal Ganglia Diseases; Benzazepines; Clozapine; Dopamine Antagonists; Female; Humans; Iodine Radioisotopes; Male; Putamen; Raclopride; Receptors, Dopamine; Salicylamides; Schizophrenia; Tomography, Emission-Computed

1992
Seizure with low doses of clozapine.
    The American journal of psychiatry, 1992, Volume: 149, Issue:10

    Topics: Basal Ganglia Diseases; Clozapine; Haloperidol; Schizophrenia; Schizophrenic Psychology; Seizures

1992
Clozapine decreases enkephalin mRNA in rat striatum.
    Neuroscience letters, 1992, Feb-17, Volume: 136, Issue:1

    Typical antipsychotic drugs (i.e. haloperidol) induce extrapyramidal movement disorders while 'atypical' antipsychotics (i.e. clozapine) do not. In situ hybridization histochemistry followed by film autoradiography showed that clozapine treatment (20 mg/kg i.p. daily for 28 days) decreased the level of labelling for preproenkephalin mRNA in the striatum of the rat while haloperidol treatment (1 mg/kg i.p. daily for 28 days) resulted in no change compared with controls. The results suggest that these typical and atypical antipsychotic drugs exert differential effects on the enkephalin-containing striatal projection to the globus pallidus, a pathway critical for the expression of extrapyramidal movement disorders.

    Topics: Animals; Basal Ganglia Diseases; Clozapine; Corpus Striatum; Depression, Chemical; Efferent Pathways; Enkephalins; Gene Expression Regulation; Globus Pallidus; Haloperidol; Male; Nucleic Acid Hybridization; Protein Precursors; Rats; Rats, Inbred Strains

1992
Tolerability of long term clozapine treatment.
    Psychopharmacology, 1989, Volume: 99 Suppl

    Tolerability of long term clozapine treatment (7-8 years) was investigated in 27 female patients (age 34-77 years). Diagnosis according to ICD 9 was schizophrenia in 21 patients, severe psychomotor agitation with mental deficiency in 4 patients and an "endogenous" depression in 2 patients. All patients had previously been treated with different neuroleptics but with inadequate response or distressing side effects. The duration of the disorder was 10-36 years, duration of hospitalisation 10-36 years. At the day of investigation the total dose of clozapine ranged from 52-826 g, the average total dose being 385 g. The daily dose of clozapine ranged from 75 to 600 mg, the average daily dose being 225 mg. Only 2 patients were treated exclusively with clozapine, the other 25 patients were also receiving other neuroleptics. Seventy eight per cent of the investigated patients complained about hypersalivation and 63% showed overweight. In 37% of the patients the EEG demonstrated abnormalities. Mild parkinsonism was reported in 15% and akathisia in 11% of the patients, all these patients being on combined treatment. Clozapine did not induce tardive dysakinesia (TD) in any of the patients within a treatment period of 7-8 years. It is concluded that a potential benefit of clozapine includes a low incidence of neurological side effects even after long term administration.

    Topics: Adult; Aged; Basal Ganglia Diseases; Clozapine; Dibenzazepines; Drug Tolerance; Electroencephalography; Female; Humans; Middle Aged; Psychiatric Status Rating Scales; Schizophrenia; Schizophrenic Psychology

1989
1-[3-(Diarylamino)propyl]piperidines and related compounds, potential antipsychotic agents with low cataleptogenic profiles.
    Journal of medicinal chemistry, 1985, Volume: 28, Issue:5

    On the basis of a structural model of the postsynaptic dopaminergic antagonist pharmacophore, a series of 1-[3-(diarylamino)propyl]piperidines and related compounds was synthesized and evaluated for potential antipsychotic activity. For a rapid measure of activity, the target compounds were initially screened in vitro for inhibition of [3H]haloperidol binding and in vivo in a test of locomotor activity. Behavioral efficacy of compounds identified from the initial screens was more accurately measured in rats by using a suppression of high base-line medial forebrain bundle self-stimulation test model. The propensity of these compounds for causing extrapyramidal side effects was evaluated by using a rat catalepsy method. On the basis of these test models, we have shown that the methine carbon of the 1-(4,4-diarylbutyl)piperidines can be advantageously replaced with a nitrogen atom. The 1-[3-(diarylamino)propyl]piperidines were less cataleptic than the corresponding 1-(4,4-diarylbutyl)piperidines. The compounds with the widest separation between efficacious dose and cataleptic dose are 8-[3-[bis(4-fluorophenyl)amino]propyl]-1-phenyl-1,3,8-triazaspiro [4. 5]decan-4-one (6), 1-[1-[3-[bis(4-fluorophenyl)amino]propyl]-4-piperidinyl]-1,3-dihydro- 2H-benzimidazol-2-one (11), 1-[1-[3-[bis(4-fluorophenyl)amino]propyl]-1,2,3,6-tetrahydro-4- pyridinyl]-1,3-dihydro-2H-benzimidazol-2-one (22), and 1-[3-[bis(4-fluorophenyl)amino]propyl]-4-(2-methoxyphenyl)piperazine (26).

    Topics: Animals; Antipsychotic Agents; Basal Ganglia Diseases; Binding, Competitive; Catalepsy; Corpus Striatum; Haloperidol; Humans; In Vitro Techniques; Male; Mice; Motor Activity; Piperazines; Piperidines; Rats; Receptors, Dopamine; Self Stimulation; Structure-Activity Relationship

1985
Neuroleptic-induced acute dyskinesias in squirrel monkeys: correlation with propensity to cause extrapyramidal side effects.
    Psychopharmacology, 1980, Volume: 68, Issue:1

    In squirrel monkeys that had undergone repeated treatment with haloperidol at intervals of 7--14 days, subsequent acute administration of haloperidol induced dystonia and dyskinesias. This acute effect of haloperidol was dose-related and occurred at the same doses that impaired Sidman avoidance performance. Chlorpromazine, fluphenazine, metoclopramide, tetrabenazine, and Su-23397, all of which have been associated with extrapyramidal side effects, reliably elicited dyskinesias in these monkeys. Dyskinesias were less mared after thioridazine and absent after clozapine, corresponding to the reported lower incidence of extrapyramidal side effects in the clinic. The non-neuroleptics, baclofen, and diazepam, failed to elicit dyskinesias. In contrast to the dyskinetic syndrome, the incidence of catalepsy or tremor did not accurately predict propensity to elicit extrapyramidal symptomatology. The acute dyskinetic syndrome in squirrel monkeys may therefore serve as an animal model for predicting the ability of antipsychotics to cause extrapyramidal dysfunction, and may yield insight into the mechanisms of these drug-induced motor disorders.

    Topics: Animals; Antipsychotic Agents; Avoidance Learning; Baclofen; Basal Ganglia Diseases; Clozapine; Diazepam; Dyskinesia, Drug-Induced; Haloperidol; Haplorhini; Male; Saimiri

1980
Clozapine-like drugs.
    Psychopharmacology bulletin, 1980, Volume: 16, Issue:3

    Topics: Animals; Antipsychotic Agents; Basal Ganglia Diseases; Clozapine; Humans

1980
[Norepinephrine turnover under neuroleptic treatment of schizophrenic syndromes (author's transl)].
    Arzneimittel-Forschung, 1978, Volume: 28, Issue:9

    In 45 psychotic in-patients with the paranoid-hallucinatory syndrome, the psychopathology, the extrapyramidal motor disturbances and 3-methoxy-4-hydroxy-phenylethyleneglycol (MHPG) in CSF were investigated. A 15-day treatment with haloperidol induced significant increase of MHPG in CSF; after 10 days clozapine treatment MHPG was significantly reduced. 10 days later the normal values were reached again. The investigation of MHPG in CSF under treatment with neuroleptics showed no correlation between antipsychotic activity and the turnover of central norepinephrine.

    Topics: Adult; Antipsychotic Agents; Basal Ganglia Diseases; Clozapine; Haloperidol; Humans; Methoxyhydroxyphenylglycol; Middle Aged; Norepinephrine; Schizophrenia

1978
Anticholinergic properties of antipsychotic drugs and their relation to extrapyramidal side-effects.
    Psychopharmacology, 1976, Dec-21, Volume: 51, Issue:1

    The effects of haloperidol, alone and in combination with atropine, were compared with the effects of clozapine, alone and in combination with physostigmine, in a variety of tests commonly used to characterize neuroleptic compounds. It was found that clozapine in combination with physostigmine did not present the profile of activity of a classical neuroleptic agent; neither did haloperidol in combination with atropine present that of clozapine. In fact, some effects of haloperidol (catalepsy) were antagonized by atropine, while others (induction of striatal DA-receptor hypersensitivity) were enhanced. It is concluded that the interaction between dopaminergic and cholinergic systems in the striatum is highly complex, and that a neuroleptic possessing both potent DA-receptor blocking and muscarinic anticholinergic activity, while being less likely to cause parkinsonism in patients, would be more likely to induce tardive dyskinesias.

    Topics: Animals; Antipsychotic Agents; Atropine; Basal Ganglia Diseases; Clozapine; Corpus Striatum; Drug Interactions; Dyskinesia, Drug-Induced; Female; Haloperidol; Homovanillic Acid; Male; Parasympathetic Nervous System; Physostigmine; Rats; Receptors, Dopamine; Receptors, Muscarinic

1976
[Letter: Discussion contribution to the article "Extrapyramidal symptoms during Clozapin therapy. A case contribution" by S. Doepp and C. Buddeberg, Nervenarzt 46, 589-590 (1975)].
    Der Nervenarzt, 1976, Volume: 47, Issue:5

    Topics: Animals; Basal Ganglia Diseases; Clozapine; Dibenzazepines; Humans; Long-Term Care; Receptors, Drug

1976
[On the problem of side effects of clozapin (author's transl)].
    Ceskoslovenska psychiatrie, 1976, Volume: 72, Issue:1

    Topics: Basal Ganglia Diseases; Clozapine; Dibenzazepines; Fever; Headache; Humans

1976
Clozapine: a new and unusual antipsychotic agent.
    Psychopharmacology bulletin, 1975, Volume: 11, Issue:1

    Topics: Anti-Anxiety Agents; Basal Ganglia Diseases; Benzodiazepines; Clozapine; Dibenzazepines; Handwriting; Humans; Psychiatric Status Rating Scales; Psychotic Disorders

1975
On the significance of the increase in homovanillic acid (HVA) caused by antipsychotic drugs in corpus striatum and limbic forebrain.
    Psychopharmacologia, 1975, Aug-21, Volume: 43, Issue:2

    The effect of various antipsychotic drugs on the blockade of dopaminergic receptors in striatum and limbic forebrain was examined by establishing dose-response curves for the increase in HVA and for the antagonism of d-amphetamine-induced rotation in rats with unilateral lesions of the substantia nigra. A good quantitative correlation was found between dopaminergic blockade in the striatum as reflected by the ED100 for striatal HVA increase and the ED50 for rotational antagonism and the occurrence of extrapyramidal side effects in man. The ED100 for the increase in HVA in the limbic forebrain showed the same rank order of potency as those in the striatum: Haloperidol greater than primozide greater than chlorpromazine greater than thioridazine greater than clozapine. The results thus demonstrate a very good correlation between the degree of dopaminergic blockade and the increase of extrapyramidal side effects in man, but suggest the possibility of a dissociation between dopaminergic blockade and antipsychotic activity.

    Topics: Animals; Antipsychotic Agents; Basal Ganglia Diseases; Chlorpromazine; Clozapine; Corpus Striatum; Dextroamphetamine; Dopamine; Dose-Response Relationship, Drug; Haloperidol; Homovanillic Acid; Humans; Limbic System; Male; Phenylacetates; Pimozide; Rats; Receptors, Drug; Rotation; Stereotyped Behavior; Substantia Nigra; Thioridazine

1975
[Extrapyramidal symptoms following Clozapine therapy. Case report].
    Der Nervenarzt, 1975, Volume: 46, Issue:10

    Topics: Acetylcholine; Basal Ganglia Diseases; Chorea; Clozapine; Diagnosis, Differential; Dibenzazepines; Drug Synergism; Humans; Hyperkinesis; Long-Term Care; Male; Middle Aged; Movement Disorders; Parasympatholytics; Schizophrenia, Paranoid; Substance Withdrawal Syndrome; Tranquilizing Agents

1975
[Biogenic amines and schizophrenia].
    Schweizerische medizinische Wochenschrift, 1975, Sep-20, Volume: 105, Issue:38

    Three main biogenic amine hypotheses for the origin of schizophrenia are discussed. The dopamine theory of schizophrenia postulates a pathogenetic connection between the disease and changes in the activity of dopaminergic cells in the brain. The theory is mainly based on findings on the mechanism of action of neuroleptics, on the clinical features and pharmacology of the amphetamine psychosis, and on some amphetamine effects in animals. Several results are in good agreement with the assumption of a state of hyperactivity of central dopamine neurons, whereas others, e.g. the lack of an increased dopamine turnover, are not. According to another theory, schizophrenia is caused by reversible damage to central norepinephrine cells. So far the only empirical basis for this theory is the finding that the activity of dopamine-beta-hydroxylase, a marker enzyme for noradrenaline cells, is lowered in the brains of schizophrenic patients. Thus further confirmation is required. The transmethylation hypotheses assume that hallucinogenic amine metabolites are produced in the body and lead to the appearance of schizophrenic symptoms. Whether or not the occurrence of DMPEA, presumably an oxymethylation product of the dopamine metabolism, is specific for schizophrenics is still open to question; if it is, the meaning of this finding is obscure. Current results leave open the possibility that N-dimethyltryptamine or other N-methylated hallucinogenic biogenic amine metabolites cause the disease; however, this hypothesis is hardly confirmed by positive empirical results.

    Topics: Amphetamines; Basal Ganglia Diseases; Clozapine; Dopamine; Dopamine beta-Hydroxylase; Humans; N,N-Dimethyltryptamine; Parkinson Disease, Secondary; Receptors, Adrenergic; Schizophrenia; Tranquilizing Agents

1975
Clozapine--a potential antipsychotic agent without extrapyramidal manifestations.
    Psychopharmacology bulletin, 1975, Volume: 11, Issue:1

    Topics: Basal Ganglia Diseases; Clozapine; Dibenzazepines; Humans; Psychiatric Status Rating Scales; Psychotic Disorders

1975
[Clinical experience with Leponex].
    Psychiatrie, Neurologie, und medizinische Psychologie, 1975, Volume: 27, Issue:6

    Until now the "neuroleptic threshold" (Haase) was considered to be the efficiency criterion of the antipsychotic effect of a neuroleptic substance and it was thought therefore that the extrapyramidal symptoms were a necessary although undesired side effect. The benodiazepine derivative Leponex developed by Sandox - Basel upsets this view because it has an excellent antipsychotic effect without creating definite extrapyramidal symptoms. It is noted for its quick soporfic effect after only a few minutes, for subdueing psychopathological productivity in a very impressive way, for acting rapidly on the "plus"-symptomatology typical of psychosis, as early as in the first days of treatment, and for its equally visible effect on the "minus"-symptoms, typical of psychosis, in the last third of an average period of treatment lasting 40 days. The clinic using Leponex (Dresden, Halle, Brandenburg-Görden) belonged to the clinical application programme of the Sandox - Basel firm. The article gives a summary of essential results and particulars about the treatment. A detailed evaluation of the case sheets which are at present being statistically reviewed will be given in the next paper.

    Topics: Adult; Basal Ganglia Diseases; Bipolar Disorder; Clozapine; Dibenzazepines; Humans; Schizophrenia; Time Factors

1975
Inhibition of circling behavior by neuroleptic drugs in mice with unilateral 6-hydroxydopamine lesions of the striatum.
    Psychopharmacologia, 1975, Dec-31, Volume: 45, Issue:2

    The development of circling behavior to apomorphine, amphetamine and L-Dopa in mice with unilateral 6-hydroxydopamine lesions of the dopaminergic nerve terminals in the striatum has been studied, and the effect of a range of neuroleptic and sedative drugs on this circling behaviour has been investigated. Circling induced by all the stimulant drugs was inhibited in a dose-dependent manner by haloperidol, pimozide, chlorpromazine, metoclopramide and clozapine (in descending rank order of potency), but not by phenoxybenzamine, diazepam, promethazine and pentobarbitone sodium. This relatively simple animal model appears useful for screening neuroleptic drugs which may block striatal dopamine receptors, thereby predicting their potency to cause unwanted extrapyramidal effects but not their antipsychotic efficacy.

    Topics: Animals; Apomorphine; Basal Ganglia Diseases; Behavior; Biogenic Amines; Bis(4-Methyl-1-Homopiperazinylthiocarbonyl)disulfide; Chlorpromazine; Clozapine; Corpus Striatum; Dextroamphetamine; Diazepam; Dopamine; Haloperidol; Humans; Hydroxydopamines; Levodopa; Male; Metoclopramide; Mice; Motor Activity; Pentobarbital; Phenoxybenzamine; Pimozide; Promethazine; Stereotyped Behavior; Tranquilizing Agents

1975
Antischizophrenic drugs: affinity for muscarinic cholinergic receptor sites in the brain predicts extrapyramidal effects.
    Journal of psychiatric research, 1974, Volume: 11

    Topics: Animals; Antipsychotic Agents; Basal Ganglia Diseases; Binding, Competitive; Brain; Chlorpromazine; Clozapine; Fluphenazine; Guinea Pigs; Haloperidol; Haplorhini; Humans; In Vitro Techniques; Perphenazine; Phenothiazines; Promazine; Rats; Receptors, Cholinergic; Schizophrenia; Thioridazine; Trifluoperazine; Triflupromazine

1974