olanzapine and sertindole

The dose-response relationships of antipsychotic drugs for schizophrenia are not well defined, but such information would be important for decision making by clinicians. The authors sought to fill this gap by conducting dose-response meta-analyses.. A search of multiple electronic databases (through November 2018) was conducted for all placebo-controlled dose-finding studies for 20 second-generation antipsychotic drugs and haloperidol (oral and long-acting injectable, LAI) in people with acute schizophrenia symptoms. Dose-response curves were constructed with random-effects dose-response meta-analyses and a spline model. The outcome measure was total score reduction from baseline on the Positive and Negative Syndrome Scale or the Brief Psychiatric Rating Scale. The authors identified 95% effective doses, explored whether higher or lower doses than the currently licensed ones might be more appropriate, and derived dose equivalencies from the 95% effective doses.. Sixty-eight studies met the inclusion criteria. The 95% effective doses and the doses equivalent to 1 mg of oral risperidone, respectively, were as follows: amisulpride for patients with positive symptoms, 537 mg/day and 85.8 mg; aripiprazole, 11.5 mg/day and 1.8 mg; aripiprazole LAI (lauroxil), 463 mg every 4 weeks and 264 mg; asenapine, 15.0 mg/day and 2.4 mg; brexpiprazole, 3.36 mg/day and 0.54 mg; haloperidol, 6.3 mg/day and 1.01 mg; iloperidone, 20.13 mg/day and 3.2 mg; lurasidone, 147 mg/day and 23.5 mg; olanzapine, 15.2 mg/day and 2.4 mg; olanzapine LAI, 277 mg every 2 weeks and 3.2 mg; paliperidone, 13.4 mg/day and 2.1 mg; paliperidone LAI, 120 mg every 4 weeks and 1.53 mg; quetiapine, 482 mg/day and 77 mg; risperidone, 6.3 mg/day and 1 mg; risperidone LAI, 36.6 mg every 2 weeks and 0.42 mg; sertindole, 22.5 mg/day and 3.6 mg; and ziprasidone, 186 mg/day and 30 mg. For amisulpride and olanzapine, specific data for patients with predominant negative symptoms were available. The authors have made available on their web site a spreadsheet with this method and other updated methods that can be used to estimate dose equivalencies in practice.. In chronic schizophrenia patients with acute exacerbations, doses higher than the identified 95% effective doses may on average not provide more efficacy. For some drugs, higher than currently licensed doses might be tested in further trials, because their dose-response curves did not plateau.

Topics: Acute Disease; Administration, Oral; Antipsychotic Agents; Aripiprazole; Clozapine; Delayed-Action Preparations; Dose-Response Relationship, Drug; Haloperidol; Humans; Imidazoles; Indoles; Isoxazoles; Lurasidone Hydrochloride; Olanzapine; Paliperidone Palmitate; Piperazines; Piperidines; Quetiapine Fumarate; Quinolones; Risperidone; Schizophrenia; Schizophrenic Psychology; Thiazoles; Thiophenes

There are many psychotropic drugs available for treatment of schizophrenia. The clinician's choice of the most effective first-line antipsychotic treatment for patients with schizophrenia should balance considerations of differential efficacy of antipsychotics against the relative risk of different side effects.. We reviewed recent studies using meta-analytic techniques and additional studies of new antipsychotics which quantitatively evaluate the efficacy of side effects of first- and second-generation antipsychotics and studies of the efficacy on add-on secondary medications. We present an integrated summary of these results to guide a clinician's decision-making.. Recent meta-analyses have suggested that antipsychotics are not equivalent in efficacy. Clozapine (effect size [SMD] 0.88 vs. placebo), amisulpride (effect size 0.6 vs placebo), olanzapine (effect size 0.59 vs. placebo), and risperidone (effect size 0.56 vs placebo) show small but statistically significant differences compared to a number of other antipsychotics on measures of overall efficacy (effect sizes 0.33-0.50). However, increasing placebo response remains a concern in interpreting these data. Amisulpride (effect size 0.47 vs placebo) and cariprazine (effect size in one trial compared to risperidone 0.29) have the strongest evidence indicating greater efficacy for treating primary negative symptoms relative to other antipsychotics. In terms of side effects, clozapine and olanzapine have among the highest weight gain potential and sertindole and amisulpride have more effects on QTc prolongation than other commonly used antipsychotics. Prolactin elevation is highest with paliperidone, risperidone, and amisulpride. Adjunctive treatment with an antidepressant drug may improve response in patients with schizophrenia who also have severe depressive or negative symptoms. For multi-episode patients with an inadequate response to an adequate dose and duration of the initial antipsychotic choice, switching to another antipsychotic, with a different receptor profile, may improve response, although evidence is very limited. In first-episode patients, a recent study on switching to another antipsychotic, with a different receptor profile after 4 weeks demonstrated no beneficial effects. There is little evidence to support using doses above the therapeutic range other than in exceptional circumstances.. Our review of recent studies using meta-analytic techniques has provided evidence that all antipsychotics are not equal in the severity of different side effects and in some measures of clinical efficacy. Comparative analysis and rankings from network meta-analyses can provide guidance to clinicians in choosing the most appropriate antipsychotic for first-line treatment, if used in conjunction with available information of the patient's history of previous clinical response or higher risks for specific side effects.

Topics: Amisulpride; Antidepressive Agents; Antipsychotic Agents; Clozapine; Depression; Humans; Imidazoles; Indoles; Olanzapine; Piperazines; Risperidone; Schizophrenia; Schizophrenic Psychology; Treatment Outcome

In many countries of the industrialised world second-generation ("atypical") antipsychotics (SGAs) have become the first line drug treatment for people with schizophrenia. The question as to whether and if so how much the effects of the various SGAs differ is a matter of debate. In this review we examined how the efficacy and tolerability of risperidone differs from that of other SGAs.. To evaluate the effects of risperidone compared with other atypical antipsychotics for people with schizophrenia and schizophrenia-like psychosis.. 1. Electronic searching We searched the Cochrane Schizophrenia Group Trials Register (April 2007) which is based on regular searches of BIOSIS, CENTRAL, CINAHL, EMBASE, MEDLINE and PsycINFO.2. Reference searching We inspected the references of all identified studies for more trials.3. Personal contact We contacted the first author of each included study for missing information.4. Drug companies We contacted the manufacturers of all atypical antipsychotics included for additional data.. We included all randomised, blinded trials comparing oral risperidone with oral forms of amisulpride, aripiprazole, clozapine, olanzapine, quetiapine, sertindole, ziprasidone or zotepine in people with schizophrenia or schizophrenia-like psychosis.. We extracted data independently. For dichotomous data we calculated risk ratio (RR) and their 95% confidence intervals (CI) on an intention-to-treat basis based on a random-effects model. We calculated numbers needed to treat/harm (NNT/NNH) where appropriate. For continuous data, we calculated mean differences (MD), again based on a random-effects model.. The review currently includes 45 blinded RCTs with 7760 participants. The number of RCTs available for each comparison varied: four studies compared risperidone with amisulpride, two with aripiprazole, 11 with clozapine, 23 with olanzapine, eleven with quetiapine, two with sertindole, three with ziprasidone and none with zotepine. Attrition from these studies was high (46.9%), leaving the interpretation of results problematic. Furthermore, 60% were industry sponsored, which can be a source of bias.There were few significant differences in overall acceptability of treatment as measured by leaving the studies early. Risperidone was slightly less acceptable than olanzapine, and slightly more acceptable than ziprasidone in this regard.Risperidone improved the general mental state (PANSS total score) slightly less than olanzapine (15 RCTs, n = 2390, MD 1.94 CI 0.58 to 3.31), but slightly more than quetiapine (9 RCTs, n = 1953, MD -3.09 CI -5.16 to -1.01) and ziprasidone (3 RCTs, n = 1016, MD -3.91 CI -7.55 to -0.27). The comparisons with the other SGA drugs were equivocal. Risperidone was also less efficacious than olanzapine and clozapine in terms of leaving the studies early due to inefficacy, but more efficacious than ziprasidone in the same outcome.Risperidone produced somewhat more extrapyramidal side effects than a number of other SGAs (use of antiparkinson medication versus clozapine 6 RCTs, n = 304, RR 2.57 CI 1.47 to 4.48, NNH 6 CI 33 to 3; versus olanzapine 13 RCTs, n = 2599, RR 1.28 CI 1.06 to 1.55, NNH 17 CI 9 to 100; versus quetiapine 6 RCTs, n = 1715, RR 1.98 CI 1.16 to 3.39, NNH 20 CI 10 to 100; versus ziprasidone 2 RCTs, n = 822, RR 1.42 CI 1.03 to 1.96, NNH not estimable; parkinsonism versus sertindole 1 RCT, n = 321, RR 4.11 CI 1.44 to 11.73, NNH 14 CI 100 to 8). Risperidone also increased prolactin levels clearly more than all comparators, except for amisulpride and sertindole for which no data were available.Other adverse events were less consistently reported, but risperidone may well produce more weight gain and/or associated metabolic problems than amisulpride (weight gain: 3 RCTs, n = 585, MD 0.99 CI 0.37 to 1.61), aripiprazole (cholesterol increase: 1 RCT, n = 83, MD 22.30 CI 4.91 to 39.69) and ziprasidone (cholesterol increase 2 RCTs, n = 767, MD 8.58 CI 1.11 to 16.04) but less than clozapine (weight gain 3 RCTs n = 373, MD -3.30 CI -5.65 to -0.95), olanzapine (weight gain 13 RCTs, n = 2116, MD -2.61 CI -3.74 to -1.48), quetiapine (ch. Risperidone seems to produce somewhat more extrapyramidal side effects and clearly more prolactin increase than most other SGAs. It may also differ from other compounds in efficacy and in the occurrence of other adverse effects such as weight gain, metabolic problems, cardiac effects, sedation and seizures. Nevertheless, the large proportion of participants leaving studies early and incomplete reporting of outcomes makes it difficult to draw firm conclusions. Further large trials, especially comparing risperidone with those other new drugs for which only a few RCTs are available, are needed.

Topics: Amisulpride; Antipsychotic Agents; Aripiprazole; Benzodiazepines; Clozapine; Dibenzothiazepines; Humans; Imidazoles; Indoles; Olanzapine; Piperazines; Quetiapine Fumarate; Quinolones; Randomized Controlled Trials as Topic; Risperidone; Schizophrenia; Sulpiride; Thiazoles

The possible side effects of antipsychotics are extensive, varied, frequently, intolerable, too often serious and sometimes fatal. The knowledge about pharmacoepidemiological and toxicological aspects of atypical neuroleptics usage is very important in clinical practice. In this paper we described practical information about side effects, toxicological profile and unwanted drug interactions of atypical neuroleptics.

Topics: Antipsychotic Agents; Benzodiazepines; Clozapine; Drug Interactions; Humans; Imidazoles; Indoles; Olanzapine

The metabolic side effects of second-generation antipsychotics (SGA) are serious and have not been compared head to head in a meta-analysis. We conducted a meta-analysis of studies comparing the metabolic side effects of the following SGAs head-to-head: amisulpride, aripiprazole, clozapine, olanzapine, quetiapine, risperidone, sertindole, ziprasidone, zotepine.. We searched the register of the Cochrane schizophrenia group (last search May 2007), supplemented by MEDLINE and EMBASE (last search January 2009) for randomized, blinded studies comparing the above mentioned SGA in the treatment of schizophrenia or related disorders. At least three reviewers extracted the data independently. The primary outcome was weight change. We also assessed changes of cholesterol and glucose. The results were combined in a meta-analysis.. We included 48 studies with 105 relevant arms. Olanzapine produced more weight gain than all other second-generation antipsychotics except for clozapine where no difference was found. Clozapine produced more weight gain than risperidone, risperidone more than amisulpride, and sertindole more than risperidone. Olanzapine produced more cholesterol increase than aripiprazole, risperidone and ziprasidone. (No differences with amisulpride, clozapine and quetiapine were found). Quetiapine produced more cholesterol increase than risperidone and ziprasidone. Olanzapine produced more increase in glucose than amisulpride, aripiprazole, quetiapine, risperidone and ziprasidone; no difference was found with clozapine.. Some SGAs lead to substantially more metabolic side effects than other SGAs. When choosing an SGA for an individual patient these side effects with their potential cause of secondary diseases must be weighed against efficacy and characteristics of the individual patient.

Topics: Amisulpride; Antipsychotic Agents; Aripiprazole; Benzodiazepines; Blood Glucose; Cholesterol; Clinical Trials as Topic; Clozapine; Dibenzothiazepines; Humans; Imidazoles; Indoles; Olanzapine; Piperazines; Quetiapine Fumarate; Quinolones; Risperidone; Schizophrenia; Sulpiride; Thiazoles; Weight Gain

Weight overload and obesity became these last years a major health problem. However gain weight is a frequent side effect of a large number of psychotropics. This article proposes to discuss this potential while reviewing various molecules. This reveals that the atypical antipsychotics are most likely to induce weight gain, in particular clozapine and olanzapine. The tricyclic antidepressants and mirtazapine come next, with the majority of the mood stabilizers. The old antipsychotics seem to involve less gain of weight. The SSRI make lose weight in the first weeks of treatment, but induce a moderate weight gain on the long term.

Topics: Adolescent; Adult; Amisulpride; Antidepressive Agents; Antimanic Agents; Antipsychotic Agents; Aripiprazole; Benzodiazepines; Body Mass Index; Child; Clozapine; Dibenzothiazepines; Double-Blind Method; Female; Fructose; Haloperidol; Humans; Imidazoles; Indoles; Male; Obesity; Olanzapine; Piperazines; Placebos; Psychotropic Drugs; Quetiapine Fumarate; Quinolones; Randomized Controlled Trials as Topic; Risperidone; Socioeconomic Factors; Sulpiride; Thiazoles; Time Factors; Topiramate; Valproic Acid; Weight Gain

Both first-generation and second-generation antipsychotic medications can lower the seizure threshold, increasing the chances of seizure induction. This article reviews the published literature concerning the seizure-lowering effects of first- and second-generation antipsychotic medication. Unfortunately, rigorously controlled studies are relatively infrequent, and case reports form a large part of the available literature, limiting the confidence with which firm conclusions can be drawn. Of the first-generation antipsychotic medications, chlorpromazine appears to be associated with the greatest risk of seizure provocation, although other first-generation antipsychotics also lower seizure threshold. Conversely, molindone, haloperidol, fluphenazine, pimozide and trifluoperazine are associated with a lower risk of seizure induction. Clozapine is the second-generation antipsychotic most frequently associated with seizures, with risperidone appearing to confer a relatively low risk. Other factors such as history of seizure activity, concurrent use of other drugs that lower seizure threshold, rapid dose titration, slow drug metabolism, metabolic factors and drug-drug interactions appear to increase the chances of an antipsychotic medication inducing seizure activity.

Topics: Antipsychotic Agents; Aripiprazole; Benzodiazepines; Clinical Trials as Topic; Clozapine; Dibenzothiazepines; Humans; Imidazoles; Indoles; Olanzapine; Piperazines; Pirenzepine; Quetiapine Fumarate; Quinolones; Risperidone; Seizures; Thiazoles

During 20th century serious mental disorders were divided into two groups according symptomatology and course of disorder. Individuals with dominating disturbance of perception, thinking and cognition were basically diagnosed having schizophrenic. Individuals with mood disturbance were basically diagnosed having affective disorders. However, there were patients who did not fit neatly into either category. In 1933 Jocob Kasanin introduced the term "schizoaffective psychosis". Scientific discussions involved the possibility that schizoaffective disorder was conceptualized most accurately as following: a type of schizophrenia, a type of affective disorder, a unique disorder that was separate from both schizophrenia and bipolar disorder, an arbitrary categorization of clinical symptoms that marked a continuum between schizophrenia and affective illness, a heterogeneous collection of "interforms" between schizophrenia and affective disorders. However, diagnosis of schizoaffective disorder is included both in DSM-IV-TR and ICD-10. Schizoaffective disorder is listed in the category "schizophrenia and other psychotic disorders". The differential diagnosis includes basically either schizophrenia or affective disorder. The epidemiological status of schizoaffective disorder is somewhat uncertain compared with schizophrenia because of dilemmas related to diagnosis and classification of the disorder. Treatment of schizoaffective disorder comprises psychotropic medication, supportive psychotherapy, social care, rehabilitation. The most important groups of psychotropic medications are: antipsychotics, antidepressants and mood stabilizers. Atypical antipsychotics are the first-line medication for schizoaffective disorder due to their pharmacological properties. In the case of schizoaffective disorders combination of atypical antipsychotics with antidepressants seems to be useful. Novel antidepressants have priority for the combination mentioned above. Peculiarities of mechanism of action of antidepressant are important for combinations. Mood stabilizers seem to be useful for treatment of certain type of schizoaffective disorder as well.

Topics: Adolescent; Amisulpride; Animals; Antidepressive Agents; Antidepressive Agents, Tricyclic; Antimanic Agents; Antipsychotic Agents; Benzodiazepines; Carbamazepine; Child; Diagnosis, Differential; Dibenzothiazepines; Dogs; Female; Humans; Imidazoles; Indoles; Lithium Carbonate; Male; Mianserin; Middle Aged; Mirtazapine; Olanzapine; Piperazines; Pirenzepine; Placebos; Prognosis; Psychotic Disorders; Quetiapine Fumarate; Randomized Controlled Trials as Topic; Risperidone; Sulpiride; Thiazoles; Time Factors

"Atypical" antipsychotics represent a new generation of antipsychotics with a significantly lower incidence of extrapyramidal side effects (EPS), as well as little or no effect on prolactin elevation. These advantages constitute a major improvement in the treatment of patients with schizophrenia. The exact mechanisms that make these drugs atypical is not clear. However, a preferential action on serotonin 5-HT2 or D4 receptors, or a more rapid dissociation from the dopamine D2 receptor, may account for atypicality. Although the atypical antipsychotics have overcome EPS, other side effects such as weight gain and impaired glucose tolerance/lipid abnormalities have come to the fore. Thus, the challenges are far from over. The current atypicals are much more effective against the psychosis of schizophrenia than against the other, more enduring aspects of this disorder, e.g. negative symptoms and cognitive dysfunction. At present, the atypicals use a "pharmacological shotgun" strategy to treat aspects of the disease in all patients. A more sophisticated and perhaps effective approach to schizophrenia may lie in independently targeting the pathophysiological mechanisms of each clinical dimension (i.e. positive, negative, cognitive, and affective) with more selective drugs that can be combined and individually titrated to the needs of each patient.

Topics: Amisulpride; Antipsychotic Agents; Benzodiazepines; Clozapine; Dibenzothiazepines; Dibenzothiepins; Dopamine Antagonists; Drug Monitoring; Haloperidol; Humans; Imidazoles; Indoles; Olanzapine; Piperazines; Pirenzepine; Quetiapine Fumarate; Receptors, Dopamine D2; Receptors, Dopamine D4; Risperidone; Schizophrenia; Schizophrenic Psychology; Serotonin Antagonists; Sulpiride; Thiazoles; Treatment Outcome

A comprehensive evaluation of atypical antipsychotics for the treatment of schizophrenia involves documentation of clinical effectiveness, quality of life and medical cost outcomes. The results of pharmacoeconomic studies assist psychiatrists, and other healthcare decision-makers, in identifying pharmacotherapies that provide the greatest benefit to patients at the most acceptable cost. The cost-effectiveness of the newer atypical antipsychotics has been examined using clinical decision-modeling studies and randomized clinical trials. The research evidence suggests that clozapine is a cost-effective treatment for neuroleptic refractory schizophrenia. Olanzapine and risperidone may be cost-neutral or, at best, slightly cost-saving compared with conventional antipsychotics, although they do improve clinical symptoms and quality of life outcomes. There is insufficient published data on pharmacoeconomic outcomes for sertindole, quetiapine and ziprasidone to make any conclusions about their cost-effectiveness in treating schizophrenia.

Topics: Antipsychotic Agents; Benzodiazepines; Clozapine; Cost-Benefit Analysis; Dibenzothiazepines; Health Care Costs; Humans; Imidazoles; Indoles; Olanzapine; Pirenzepine; Quetiapine Fumarate; Randomized Controlled Trials as Topic; Risperidone

The results of controlled studies of the efficacy of the new atypical neuroleptics in treating negative symptoms show that these antipsychotics have a more pronounced effect on negative symptoms in acute schizophrenic patients than the classical neuroleptics. Supplementary complex statistical analyses substantiate that the increased efficacy of the atypical neuroleptics in treating negative symptoms can only partially be explained by indirect effects of better extrapyramidal tolerability, better effects on productive psychotic symptoms, etc. Instead, it is due largely to the stronger direct effect of these atypical neuroleptics. Clinical studies to evaluate their efficacy in chronic schizophrenic patients with stable, predominantly negative symptoms are still mostly lacking. First results support the presumption that atypical neuroleptics have a direct effect. Parallel to the evaluation of the new atypical neuroleptics, important progress has been made in the methodology of clinical studies in this area.

Topics: Amisulpride; Antipsychotic Agents; Benzodiazepines; Clozapine; Dibenzothiazepines; Dibenzothiepins; Double-Blind Method; Dyskinesia, Drug-Induced; Humans; Imidazoles; Indoles; Neurotransmitter Agents; Olanzapine; Piperazines; Pirenzepine; Quetiapine Fumarate; Randomized Controlled Trials as Topic; Risperidone; Schizophrenia; Schizophrenic Psychology; Sulpiride; Thiazoles

To review systematically data relating to weight changes with atypical antipsychotics.. We conducted a Medline search on October 29 1999 and covered the period 1980-99. All recovered papers were examined for further relevant reports. In addition, we wrote to pharmaceutical manufacturers and 10 practising clinicians to ask them to provide other relevant reports known to them.. Eighty reports mentioning change in body weight were retrieved. Data relating to weight changes were of variable quality. Weight changes were indicated by a variety of measures. The majority of reports related to short-term changes.. All atypical drugs, with the exception of ziprasidone, have been associated with weight increases. Clozapine seems to have the highest risk of weight gain, followed by olanzapine and quetiapine. There is probably a lower risk with risperidone, sertindole and zotepine and a still lower risk with amisulpride. Ziprasidone appears not to be associated with weight gain. In the absence of more compelling data, these rankings must be considered approximate and preliminary. Longer, more robust trials are needed.

Topics: Amisulpride; Antipsychotic Agents; Benzodiazepines; Clozapine; Dibenzothiazepines; Dibenzothiepins; Humans; Imidazoles; Indoles; Olanzapine; Piperazines; Pirenzepine; Quetiapine Fumarate; Risperidone; Sulpiride; Thiazoles; Weight Gain

To develop an evidence base for recommendations on the use of atypical antipsychotics for patients with schizophrenia.. Systematic overview and meta-regression analyses of randomised controlled trials, as a basis for formal development of guidelines.. 12 649 patients in 52 randomised trials comparing atypical antipsychotics (amisulpride, clozapine, olanzapine, quetiapine, risperidone, and sertindole) with conventional antipsychotics (usually haloperidol or chlorpromazine) or alternative atypical antipsychotics.. Overall symptom scores. Rate of drop out (as a proxy for tolerability) and of side effects, notably extrapyramidal side effects.. For both symptom reduction and drop out, there was substantial heterogeneity between the results of trials, including those evaluating the same atypical antipsychotic and comparator drugs. Meta-regression suggested that dose of conventional antipsychotic explained the heterogeneity. When the dose was

Topics: Amisulpride; Antipsychotic Agents; Benzodiazepines; Clozapine; Dibenzothiazepines; Drug Costs; Humans; Imidazoles; Indoles; Olanzapine; Pirenzepine; Quetiapine Fumarate; Regression Analysis; Risperidone; Schizophrenia; Sulpiride

The introduction of conventional antipsychotics revolutionized the management of psychotic disorders in the 1950s. The use of these agents has been marked by several shortcomings, including their association with severe motor disturbances and their limited efficacy in treating the negative and cognitive symptoms of schizophrenia. Patients noncompliance has largely been the result of subjectively distressing extrapyramidal motor side-effects (EPMS). It was therefore necessary to develop antipsychotic drugs with selective pharmacological profiles, e.g. limbic selectivity. A defining characteristic of atypical neuroleptics is a higher ratio of serotonin receptor blockade to D2 receptor blockade. Their primary advantage is their superior side-effect profile. The implications of EPMS reduction touch several domains of pathology in schizophrenia such as short- and long-term movement disorders, noncompliance, relapse rate, negative symptoms and cognitive dysfunction. Novel antipsychotics may represent the second pharmacological revolution in the treatment of psychotic disorders. There is, however, still a need for a critical evaluation of the risk-benefit-ratio of differing atypical agents.

Topics: Aged; Amisulpride; Antipsychotic Agents; Benzodiazepines; Clozapine; Controlled Clinical Trials as Topic; Dibenzothiazepines; Dibenzothiepins; Haloperidol; Humans; Imidazoles; Indoles; Multicenter Studies as Topic; Olanzapine; Piperazines; Pirenzepine; Placebos; Quetiapine Fumarate; Risperidone; Schizophrenia; Selective Serotonin Reuptake Inhibitors; Serotonin Antagonists; Sulpiride; Thiazoles

The objective of this meta-analysis is to summarize the efficacy and tolerability of the new antipsychotics risperidone, olanzapine, sertindole and quetiapine in schizophrenia compared to placebo and conventional antipsychotics. The main results are: (1) All of the 4 new drugs are more effective than placebo, but the magnitude of the effect is only moderate [mean effect size, r, of all antipsychotics vs. placebo = 0.25, with a 95% confidence interval (CI) = 0.22-0.28, n = 2477]. (2) According to the studies published to date, sertindole and quetiapine are as effective as haloperidol, and risperidone and olanzapine are slightly more effective than haloperidol in the treatment of global schizophrenic symptomatology. (3) With respect to negative symptoms, all new antipsychotics are more effective than placebo. However, contrary to widespread opinion, so is the 'conventional' antipsychotic haloperidol. Risperidone and olanzapine are slightly superior, sertindole is as effective and--according to the only study fully published to date--quetiapine is even slightly less effective than haloperidol in this regard. (4) All new antipsychotics are associated with less frequent use of antiparkinson medication than haloperidol, with risperidone appearing to have a slightly less favourable EPS-profile than the other new antipsychotics. The methodological limitations of this review, the generalizability of the results and expectations from future research are discussed.

Topics: Antipsychotic Agents; Basal Ganglia Diseases; Benzodiazepines; Dibenzothiazepines; Double-Blind Method; Haloperidol; Humans; Imidazoles; Indoles; Olanzapine; Pirenzepine; Quetiapine Fumarate; Randomized Controlled Trials as Topic; Risperidone; Schizophrenia

Soon after the introduction of antipsychotic drugs into clinical practice, these agents were observed to be capable of producing not only acute extrapyramidal ("parkinsonian") side effects, but also later occurring abnormal involuntary movements that came to be called tardive dyskinesia. Since antipsychotic drugs are used in a variety of conditions that include psychotic features, studies have attempted to determine whether specific diagnostic subgroups may experience different degrees of vulnerability to drug-induced movement disorders. This issue is important not only to inform clinical practice, but also to provide clues to pathophysiology. A number of studies suggest that patients with affective disorders are at greater risk for developing tardive dyskinesia (controlling, to the extent possible, for other relevant variables such as age, sex, length of treatment). Encouraging preliminary data with new antipsychotic drugs such as olanzapine suggest that the risk of tardive dyskinesia associated with long-term antipsychotic drug use may be substantially reduced. This would go a long way toward improving the benefit-to-risk ratio of antipsychotic drug treatment, particularly in patients with affective disorders.

Topics: Adult; Affective Disorders, Psychotic; Anticonvulsants; Antipsychotic Agents; Benzodiazepines; Bipolar Disorder; Carbamazepine; Controlled Clinical Trials as Topic; Dibenzothiazepines; Drug Administration Schedule; Dyskinesia, Drug-Induced; Female; Humans; Imidazoles; Indoles; Male; Olanzapine; Piperazines; Pirenzepine; Psychotic Disorders; Quetiapine Fumarate; Risk Assessment; Risk Factors; Risperidone; Schizophrenia; Thiazoles; Treatment Outcome

The introduction of the atypical antipsychotics clozapine, risperidone, olanzapine, quetiapine and sertindole for the treatment of schizophrenia has coincided with an increased awareness of the potential of drug-drug interactions, particularly involving the cytochrome P450 (CYP) enzymes. The current literature describing the pharmacokinetics of the metabolism of these agents, including their potential to influence the metabolism of other medications, is reviewed. Clozapine appears to be metabolized primarily by CYP1A2 and CYP3A4, with additional contributions by CYP2C19 and CYP2D6. In addition, clozapine may inhibit the activity of CYP2C9 and CYP2C19, and induce CYP1A, CYP2B and CYP3A. Risperidone is metabolized by CYP2D6, and possibly CYP3A4. In vitro data indicate that olanzapine is metabolized by CYP1A2 and CYP2D6. Quetiapine is metabolised by CYP3A4 and sertindole by CYP2D6. There is, however, a general paucity of in vivo data regarding the metabolism of the atypical antipsychotics, indicating a need for further research in this area.

Topics: Antipsychotic Agents; Benzodiazepines; Clozapine; Cytochrome P-450 Enzyme System; Dibenzothiazepines; Drug Interactions; Humans; Imidazoles; Indoles; Olanzapine; Pirenzepine; Quetiapine Fumarate; Risperidone; Schizophrenia

Since the discovery of the neuroleptics in 1952, french psychiatrists have proposed a classification of neuroleptics taking into account the pharmalogical and therapeutic differences between these drugs. They distinguished three different clinical effects of neuroleptics: sedative effects, effects on the positive symptoms of schizophrenia and effects on the negative symptoms. However these agents have many side effects including the extrapyramidal syndrome (EPS), akathisia, dystonia and parkinsonism. These side effects occur in up to 75% of patients receiving typical neuroleptics and are the main cause of non-compliance. Since the eighties, clozapine was introduced for use in refractory patients because it has a better efficacy (than haloperidol) specifically on negative symptoms, a better tolerance and fewer effects. After clozapine, several new antipsychotic agents are now available, such as risperidone, olanzapine, sertindole, quietapine, ziprasidone ... Their therapeutical effects are probably linked with a dual antagonist effect on 5HT2 and D2 receptors. The present article reviews the evolution of the use of these new agents, their real efficacy, their adverse effects and their expanding indications. Future research will more clearly establish appropriate treatment guidelines for their use. These new antipsychotics should add a positive modification in schizophrenia care and in some mood disorders. The approach consisting on individualizing dimensions and clusters analysis might be useful to test the efficiency of each antipsychotic on a syndromic dimension.

Topics: Amisulpride; Antipsychotic Agents; Benzodiazepines; Clozapine; Dibenzothiazepines; Humans; Imidazoles; Indoles; Olanzapine; Piperazines; Pirenzepine; Psychotic Disorders; Quetiapine Fumarate; Risperidone; Sulpiride; Thiazoles

Topics: Antipsychotic Agents; Benzodiazepines; Dose-Response Relationship, Drug; Humans; Imidazoles; Indoles; Olanzapine; Pirenzepine; Risk Assessment; Risperidone; Schizophrenia

As antipsychotic treatment evolves toward a broader range of efficacy and more benign side effect profiles, our criteria for treatment-refractory schizophrenia may become more subtle. Unidimensional concepts of treatment resistance may be replaced by multiaxial descriptions of the target symptoms, side effects, and compliance issues that limit the ultimate goals of enhanced psychosocial function and quality of life. Augmentation strategies, increasing insight into dose response relationships, and atypical agents may benefit patients who failed to respond to or tolerate previous therapies. The advantages of newer agents in treatment-resistant schizophrenia may arise in part from their preferential targeting of newer agents in treatment-resistant schizophrenia may arise in part from their preferential targeting of mesolimbic compared with motor and tuberoinfundibular dopaminergic pathways.

Topics: Antipsychotic Agents; Benzodiazepines; Clinical Trials as Topic; Clozapine; Diagnosis, Differential; Humans; Imidazoles; Indoles; Olanzapine; Patient Compliance; Pirenzepine; Psychiatric Status Rating Scales; Receptors, Dopamine D2; Risperidone; Schizophrenia; Schizophrenic Psychology; Terminology as Topic; Treatment Failure

The atypical antipsychotics are a new class of agents with great promise for use in the elderly because of their reduced propensity to cause acute extrapyramidal adverse effects. Treatment of older patients with these agents, however, needs to take into consideration age-related changes in pharmacokinetics and the risks of drug-drug interactions. Additionally, current evidence of their efficacy in late-life psychoses is derived largely from case series and from the extrapolation of results obtained in studies of younger patients with schizophrenia. Controlled clinical studies of atypical antipsychotics in elderly patients are urgently needed.

Topics: Aged; Aging; Antipsychotic Agents; Benzodiazepines; Clozapine; Humans; Imidazoles; Indoles; Olanzapine; Pirenzepine; Randomized Controlled Trials as Topic; Risperidone; Treatment Outcome

Traditional neuroleptics are often utilized clinically for the management of bipolar disorder. Although effective as antimanic agents, their mood stabilizing properties are less clear. Additionally, their acute clinical side effect profile and long term risk of tardive dyskinesia, particularly in mood disorder patients, portend significant liability. This review focuses on the use of atypical antipsychotics in the treatment of bipolar disorder focusing on clozapine as the prototypical agent. Although, preclinical research and clinical experience suggest that the atypical antipsychotics are distinctly different from typical antipsychotics, they themselves are heterogeneous in profiles of neuropharmacology, clinical efficacy, and tolerability. The early clinical experience of clozapine as a potential mood stabilizer suggests greater antimanic than antidepressant properties. Conversely, very preliminary clinical experience with risperidone suggests greater antidepressant than antimanic properties and some liability for triggering or exacerbating mania. Olanzapine and sertindole are under investigation in psychotic mood disorders. The foregoing agents and future drugs with atypical neuroleptic properties should come to play an increasingly important role, compared to the older classical neuroleptics, in the acute and long term management of bipolar disorder.

Topics: Antidepressive Agents; Antimanic Agents; Antipsychotic Agents; Benzodiazepines; Bipolar Disorder; Clozapine; Humans; Imidazoles; Indoles; Olanzapine; Pirenzepine; Risperidone; Trimipramine

To present aspects of preclinical and clinical pharmacology of new antipsychotic drugs and to emphasize those preclinical drug characteristics which might predict desirable clinical actions.. Review of the relevant literature and publicly presented data.. Traditional neuroleptics have considerable effectiveness in treating positive symptoms of psychosis but can cause serious motor side effects. Clozapine produces no motor side effects and delivers a unique antipsychotic action. Risperidone also produces low motor side effects, but only at relatively low doses. Olanzapine and sertindole are newly introduced. Both have potent antipsychotic actions, with greatly reduced motor side effects. Both drugs also have possible advantages in negative symptoms.. These data support the conclusion that several new antipsychotics are becoming available for general use which are safe and effective in the treatment of psychosis and have several advantages over traditional neuroleptics.

Topics: Antipsychotic Agents; Benzodiazepines; Clozapine; Humans; Imidazoles; Indoles; Olanzapine; Pirenzepine; Psychiatric Status Rating Scales; Risperidone; Schizophrenia; Schizophrenic Psychology; Treatment Outcome

Topics: Antipsychotic Agents; Benzodiazepines; Benzothiazoles; Clinical Trials as Topic; Dibenzothiazepines; Humans; Imidazoles; Indoles; Olanzapine; Piperazines; Pirenzepine; Pramipexole; Psychotic Disorders; Quetiapine Fumarate; Risperidone; Thiazoles

The unprecedented level of activity in the development of new antipsychotic medications can be traced to the 1989 approval of clozapine by the US Food and Drug Administration for treatment of refractory schizophrenia. This has encouraged the development of other new agents that share some of clozapine's receptor binding characteristics. A wide range of clinical trial designs are being used during the development of new antipsychotic medications. This article describes both basic designs and more innovative ones: flexible-dose designs that include placebo and conventional neuroleptic agents as controls; fixed-dose designs with multiple doses of experimental medication; and fixed-dose designs with multiple doses of the experimental and comparator medication. The strengths and weaknesses of each are identified. The need for long-term maintenance studies of newer agents is emphasized because psychotic disorders in general, and schizophrenia in particular, are chronic relapsing illnesses. The current status of four newer antipsychotic medications is considered: clozapine, risperidone, olanzapine, and sertindole. The importance of direct comparison among the newer antipsychotic medications in both short- and long-term trials is highlighted.

Topics: Antipsychotic Agents; Benzodiazepines; Chronic Disease; Clinical Trials as Topic; Clozapine; Drug Administration Schedule; Drug Approval; Humans; Imidazoles; Indoles; Olanzapine; Pirenzepine; Placebos; Psychotic Disorders; Recurrence; Research Design; Risperidone; Schizophrenia; Schizophrenic Psychology; Treatment Outcome; United States; United States Food and Drug Administration

Topics: Antipsychotic Agents; Benzodiazepines; Drug Administration Schedule; Humans; Imidazoles; Indoles; Olanzapine; Pirenzepine; Randomized Controlled Trials as Topic; Schizophrenia

New neuroleptic drugs are being developed for the treatment of schizophrenia and other psychoses. Clozapine and risperidone are available for general use. Sertindole and olanzapine are nearing release. Seroquel and ziprazidone are in the final stages of study. This generation of drugs will provide advantages in the area of lower motor side effects and probably in improved negative symptom treatment.

Topics: Antipsychotic Agents; Benzodiazepines; Dibenzothiazepines; Humans; Imidazoles; Indoles; Olanzapine; Piperazines; Pirenzepine; Quetiapine Fumarate; Schizophrenia; Thiazoles

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

Serotonin-dopamine antagonists (SDAs) offer the possibility of improved treatment of schizophrenia compared with conventional neuroleptics and have superior safety profiles. Clinical trial data have so far been published for only three SDAs to date, namely, risperidone, sertindole, and olanzapine. Of these, extensive data are available only for risperidone, showing that at doses of 4 to 16 mg/day, it is superior to haloperidol at 10 to 20 mg/day. Furthermore, risperidone, 6 and 16 mg/day, significantly improved negative/symptoms, whereas 20 mg/day of haloperidol was ineffective. Risperidone also appears to cause fewer extrapyrimidal symptoms (EPS) than haloperidol, 10 or 20 mg/day. Similar advantages of risperidone over perphenazine have also been found. A clinical trial of sertindole showed that, at 20 mg/day, it was equivalent to haloperidol, 16 mg/day, and caused fewer EPS. Olanzapine, a chemical derivative of clozapine, has also been shown to be superior to haloperidol (10 to 20 mg/day) at doses of 7.5 to 17.5 mg/day. In addition, at doses of 12.5 to 17.5 mg/day, olanzapine was found to have a significantly superior effect on negative symptoms over haloperidol, 10 to 20 mg/day. Doses of up to 17.5 mg/day of olanzapine also caused fewer EPS than haloperidol, 10 to 20 mg/day. There was no evidence of any leukopenia in patients treated with olanzapine in this small study (N = 335). The low EPS liability of these SDAs, combined with their efficacy, suggests that SDAs should become the mainstay of treatment for schizophrenia.

Topics: Antipsychotic Agents; Benzodiazepines; Clinical Trials as Topic; Dopamine Antagonists; Humans; Imidazoles; Indoles; Isoxazoles; Olanzapine; Piperidines; Pirenzepine; Risperidone; Schizophrenia; Serotonin Antagonists

The aim of this study was to evaluate the efficacy, safety, and tolerability of sertindole in comparison with olanzapine in patients with chronic schizophrenia who did not respond successfully to their previous treatments. Patients with schizophrenia who were at least moderately ill and had failed to respond to previous antipsychotic treatment were randomized to double-blind sertindole or olanzapine treatment. A total of 389 patients were treated, 196 with sertindole (mean dose=17 mg/day) and 193 with olanzapine (mean dose=16 mg/day). Both drugs improved all the efficacy scale scores including the Positive and Negative Syndrome Scale total score. Although sertindole failed to prove noninferiority to olanzapine in terms of reduction in PANSS total score with the last-observation-carried-forward analysis, this can be attributed to the higher withdrawal rate in the sertindole group by day 16 by which sertindole was up-titrated to the effective dose. On excluding early withdrawals, the noninferiority criterion was fulfilled, as also in the observed-case analysis. They had similar safety profiles with respect to the total incidence of adverse events. The incidence of asymptomatic QT prolongation was higher in the sertindole group. Sertindole has an efficacy and safety profile that is comparable to that of olanzapine. The slow titration schedule and lack of sedating effect of sertindole should be considered when initiating treatment with this drug.

Topics: Adolescent; Adult; Aged; Benzodiazepines; Chronic Disease; Double-Blind Method; Drug Administration Schedule; Female; Humans; Imidazoles; Indoles; Male; Middle Aged; Olanzapine; Schizophrenia; Time Factors; Treatment Failure; Treatment Outcome; Young Adult

As part of a prospective clinical study investigating the effects of atypical neuroleptics on autonomic neurocardiac function (ANF), serial standardized recordings of conventional electrocardiograms and computer-calculated measurements of 5-minute resting heart rate variability (HRV) were obtained from 51 medication-free inpatients with schizophrenia (DSM-III-R-diagnosed) before and after an average of 14.1 days of treatment with amisulpride 400 mg/day (N = 12), olanzapine 20 mg/day (N = 13), sertindole 12 mg/day (N = 13), or clozapine 100 mg/day (N = 13). Reference values for the HRV data were obtained from a large group of well-matched healthy controls (N = 70). The most important findings were the following: (1) clozapine, olanzapine, and sertindole all prolonged mean frequency-corrected QTc times, which, in the case of sertindole, proved to be significant (Wilcoxon test p <0.05); (2) sertindole and clozapine significantly increased the mean resting heart rate; and (3) only clozapine significantly reduced the parasympathetic resting tone. The results of the HRV studies are discussed considering the in vitro receptor profiles of the atypical neuroleptics under study. Potential implications for the cardiac safety and tolerance of these drugs are also discussed.

Topics: Adult; Amisulpride; Antipsychotic Agents; Autonomic Nervous System; Benzodiazepines; Clozapine; Electrocardiography; Female; Heart; Heart Rate; Humans; Imidazoles; Indoles; Male; Middle Aged; Olanzapine; Pirenzepine; Prospective Studies; Sulpiride

We performed a retrospective analysis of 122 clinical records of 92 male patients with DSM-III-R schizophrenia to examine the relative weight gain liabilities of clozapine, risperidone, olanzapine, and sertindole compared with haloperidol. We hypothesized that the unique pharmacodynamic profiles of these agents would contribute to different amounts and patterns of weight gain.. Data were analyzed to determine differences in weight gain during treatment among patients receiving 5 different drug treatments (clozapine [N = 20], olanzapine [N = 13], risperidone [N = 38], haloperidol [N = 43], and sertindole [N = 8]). Measures of maximal weight gain, final weight, and duration to maximal weight gain were calculated.. Repeated measures analyses of variance controlling for age, treatment duration, and initial weight revealed statistically significant differences between groups on all 3 measures. Clozapine and olanzapine had the greatest maximal weight gain liability (F = 4.13, df = 4,23; p = .01). Weight gain with clozapine, but not olanzapine or risperidone, appears to persist (as reflected by final weight) despite behavioral interventions (e.g., nutritional consultation, suggested exercise regimen; F = 5.69, df = 4,23; p = .003). Clozapine- and olanzapine-treated subjects appeared to gain weight over a prolonged period of time, whereas risperidone-and sertindole-treated subjects had a more limited period of weight gain (F = 2.95, df = 4,25; p = .04).. Clozapine and olanzapine caused the most weight gain, risperidone was intermediate, and sertindole had less associated weight gain than haloperidol. The relative receptor affinities of the novel antipsychotics for histamine H1 appear to be the most robust correlate of these clinical findings.

Topics: Adult; Antipsychotic Agents; Benzodiazepines; Clozapine; Double-Blind Method; Haloperidol; Humans; Imidazoles; Indoles; Male; Obesity; Olanzapine; Pirenzepine; Placebos; Retrospective Studies; Risperidone; Schizophrenia; Weight Gain

Packed with hemoglobin, an essential protein for oxygen transport, human erythrocytes are a suitable model system for testing the pleiotropic effects of lipophilic drugs. Our study investigated the interaction between antipsychotic drugs clozapine, ziprasidone, sertindole, and human hemoglobin under simulated physiological conditions. Analysis of protein fluorescence quenching at different temperatures and data obtained from the van't Hoff diagram and molecular docking indicate that the interactions are static and that the tetrameric human hemoglobin has one binding site for all drugs in the central cavity near αβ interfaces and is dominantly mediated through hydrophobic forces. The association constants were lower-moderate strength (~10

Topics: Antipsychotic Agents; Benzodiazepines; Clozapine; Humans; Molecular Docking Simulation; Olanzapine

This study was set out to examine the impact of atypical antipsychotic drugs: aripiprazole, clozapine, ziprasidone, olanzapine, quetiapine, sertindole and amisulpride on the activity of antioxidant defence enzymes in human erythrocytes in vitro.. Cu,Zn-superoxide dismutase (SOD1), catalase (CAT), selenium-dependent glutathione peroxidase and glutathione reductase activities were determined after drugs incubation with blood of 15 apparently healthy non-smoking male volunteers (ages 23-39) for 1 h at 37 °C.. A statistically significant increase in SOD1 activity was found in samples incubated with aripiprazole (p < 0.01) and quetiapine (p < 0.05) compared with incubated control. SOD1 activity profile following native polyacrylamide gel electrophoresis indicates that aripiprazole and quetiapine protect enzyme activity from inhibition with hydrogen peroxide. Our results showed that sertindole decreases activity of CAT comparing with control non-treated erythrocytes. Moreover, in sertindole treated erythrocytes, negative correlation between SOD1 and glutathione peroxidase activities was found. Increased amount of hydrogen peroxide in such situation may leave erythrocytes and transform their role in circulation from anti-oxidative to pro-oxidative.. Our results indicate that mechanism through sertindole could express its in vivo toxic effects and point toward possible (neuro)protective effects of aripiprazole and quetiapine.

Topics: Adult; Amisulpride; Antioxidants; Antipsychotic Agents; Aripiprazole; Benzodiazepines; Catalase; Clozapine; Dibenzothiazepines; Enzyme Activation; Erythrocytes; Glutathione Peroxidase; Glutathione Reductase; Humans; Imidazoles; Indoles; Male; Olanzapine; Piperazines; Quetiapine Fumarate; Quinolones; Sulpiride; Superoxide Dismutase; Superoxide Dismutase-1; Thiazoles; Treatment Outcome; Young Adult

Cognitive dysfunction in schizophrenia is associated with functional disease symptoms. The beneficial effects of second generation antipsychotic drugs on cognitive function in schizophrenic patients are controversial. In this study, we investigated the effects of the second generation antipsychotics olanzapine, sertindole and clozapine on cognitive function in the Morris water maze task in naive or MK-801-treated animals. Male balb-c mice were treated subchronically with olanzapine (1.25, 2.5 and 5mg/kg, i.p.), sertindole (0.63, 1.3, 2.5mg/kg, s.c.) or clozapine (0.5 and 1mg/kg, i.p.), and cognitive deficits were induced by MK-801 (0.2mg/kg, i.p.) administration. Water maze performance was expressed as escape latency to find the hidden platform, the time spent in target quadrant, the mean distance to platform and the swim speed. In naive mice olanzapine impaired water maze performance, whereas sertindole and clozapine had no effect while the MK-801-induced cognitive impairment was reversed by the second generation antipsychotics - olanzapine, sertindole and clozapine at the doses used. These results revealed that while olanzapine had some disturbing effects on cognitive functions in naive animals; olanzapine, sertindole and clozapine might improve cognitive deficits in schizophrenic patients.

Topics: Animals; Antipsychotic Agents; Benzodiazepines; Clozapine; Dizocilpine Maleate; Excitatory Amino Acid Antagonists; Imidazoles; Indoles; Learning; Male; Maze Learning; Memory; Mice; Mice, Inbred BALB C; Olanzapine

We investigated the effects of the second generation antipsychotics olanzapine, sertindole and clozapine on visual recognition memory using the novel object recognition (NOR) test in naive and MK-801-treated animals. The effects of drug treatment on locomotion and anxiety were also determined using the open field test. Male Balb-c mice were treated with olanzapine (0.2, 0.4 and 0.6 mg/kg; i.p.), sertindole (0.63, 1.3 and 2.5mg/kg; s.c.) or clozapine (0.5 and 1mg/kg; i.p.), and cognitive deficits were induced by MK-801 (0.2mg/kg; i.p.) administration. Olanzapine treatment decreased the ratio index in the NOR test, whereas sertindole and clozapine had no effect in naive mice. MK-801-induced cognitive impairment was reversed by treatment with olanzapine, sertindole or clozapine. While olanzapine, sertindole and clozapine had no effect on the anxiety of naive mice as determined by the open field test, MK-801 significantly increased the total distance traveled, time spent in the center zone and the velocity of the animals. MK-801-induced effects on locomotion and anxiety in the open field test were reversed by olanzapine, sertindole or clozapine treatment. The results of the present study demonstrated that olanzapine, sertindole and clozapine improved cognition in MK-801 treated mice, and indicate that these drugs have a potential to improve cognition in schizophrenia.

Topics: Animals; Antipsychotic Agents; Benzodiazepines; Clozapine; Dizocilpine Maleate; Excitatory Amino Acid Antagonists; Imidazoles; Indoles; Learning; Male; Memory Disorders; Mice; Mice, Inbred BALB C; Motor Activity; Olanzapine; Recognition, Psychology; Visual Perception

Atypical antipsychotics have similar clinical efficacy in the treatment of schizophrenia; variability in their tolerability represents the discerning factor in treatment choices. Sertindole has a relatively good tolerability profile that favours long-term patient adherence and, therefore, is associated with lower rates of relapse and rehospitalization.. A model was developed to compare the cost-effectiveness of a 5-year treatment strategy starting with sertindole versus olanzapine, risperidone, aripiprazole or the typical antipsychotic agent, haloperidol.. The model was based on published trials and local clinical practice, and considered costs from the perspective of the Swedish National Health Insurance Board.. All atypical agents were clinically superior and more cost-effective than haloperidol with a cost per quality-adjusted life year gained of approximately 490,000 Swedish kroner. Sertindole was associated with the lowest direct and indirect medical costs, driven by its tolerability profile.. Sertindole represents a useful alternative to the current treatment options available in Sweden.. The relatively good tolerability profile of sertindole translates into lower costs of schizophrenia management, primarily driven by substantially lower direct and indirect costs. Sertindole appears to be a clinically and cost-effective alternative in the management of patients with schizophrenia in Sweden.

Topics: Adult; Antipsychotic Agents; Aripiprazole; Benzodiazepines; Cost-Benefit Analysis; Economics, Pharmaceutical; Female; Haloperidol; Humans; Imidazoles; Indoles; Male; Models, Economic; National Health Programs; Olanzapine; Piperazines; Quinolones; Risperidone; Schizophrenia; Sweden

This naturalistic study aims to compare discontinuation rates for low-dose first-generation versus second-generation antipsychotics in first-episode psychotic patients.. The prescription of antipsychotic medication in 301 consecutively admitted patients with first-episode psychosis from four catchment areas is described. For the first year of inclusion a first-generation antipsychotic in low dose was recommended as the first medication. From the second year a second-generation antipsychotic was recommended as first choice. Switching was allowed when any drug was judged to be ineffective or to have serious side-effects. Switching during the first 2 years after inclusion is described.. Switching from a low-dose first-generation antipsychotic was more frequent than from a second-generation antipsychotic (90.7 vs. 58.4%). Lack of therapeutic effect and side-effects were the more frequently recorded reasons for changing in the first-generation group. Akathisia, parkinsonism, dyskinesias, dystonia and dysphoria were more often reported in patients on first-generation drugs. Weight gain and sedation were more often reported in patients on second-generation drugs.. The findings suggest a better adherence to and tolerability for second-generation antipsychotics than for low-dose first-generation antipsychotics in first-episode psychosis.

Topics: Adolescent; Adult; Aged; Antipsychotic Agents; Benzodiazepines; Chi-Square Distribution; Clopenthixol; Clozapine; Female; Humans; Imidazoles; Indoles; Kaplan-Meier Estimate; Male; Middle Aged; Olanzapine; Perphenazine; Psychotic Disorders; Risperidone; Statistics, Nonparametric; Time Factors; Young Adult

Concern has been raised about the occurrence of venous thromboembolism (VTE) during treatment with antipsychotics. However, to date, clozapine is the only antipsychotic agent for which recurring evidence supports an association with VTE. Therefore, the aim of this study was to investigate the association between antipsychotic drugs, including clozapine and VTE.. Data mining of the WHO database of adverse drug reactions (ADRs) using Bayesian statistics is in routine use for early alerting to possible ADRs. An information component measure was used to investigate the association between antipsychotic drugs and VTE reactions in the database.. A total of 754 suspected cases of VTE related to treatment with antipsychotics had been reported. After excluding cases related to clozapine, 379 cases remained. A robust association was found for the second-generation antipsychotics group but not for the high-potency, first-generation antipsychotics group or the low-potency first-generation antipsychotics group. The individual compounds with statistically significant associations were olanzapine, sertindole and zuclopenthixol. A time-dependent analysis showed that the associations were positive for these drugs in 2002, 2001 and 2003, respectively. Case analyses were undertaken after excluding ten suspected duplicate reports. Of the remaining 369 cases, 91 cases were associated with olanzapine, 9 with zuclopenthixol and 6 with sertindole.. VTE was more often reported with the antipsychotic drugs olanzapine, sertindole and zuclopenthixol than with other drugs in the WHO database. Further studies are warranted to explain this disproportional reporting. Since the associations found were based on incomplete clinical data, the results should be considered as preliminary and interpreted cautiously.

Topics: Adult; Adverse Drug Reaction Reporting Systems; Antipsychotic Agents; Bayes Theorem; Benzodiazepines; Clopenthixol; Databases, Factual; Female; Humans; Imidazoles; Indoles; Male; Middle Aged; Olanzapine; Time Factors; Venous Thromboembolism; World Health Organization; Young Adult

In the rat, selective suppression of conditioned avoidance response has been widely reported as a test with high predictive validity for antipsychotic efficacy. Recent studies have shown that the relationship between dopamine D2 receptor occupancy and the suppression of conditioned avoidance response behaviour correlates well with the relationship between human dopamine D2 receptor occupancy and clinical effect. The aim of the present study was to evaluate how pharmacokinetic/pharmacodynamic (PK/PD) predictions of therapeutic effective steady-state plasma levels by means of conditioned avoidance response behaviour in rodents, correlate with clinically relevant plasma exposure for the classical antipsychotic drug haloperidol and four second generation antipsychotics: sertindole, clozapine, risperidone and olanzapine, including selected metabolites. In order to confirm the validity of the present conditioned avoidance response procedure, in vivo striatal dopamine D2 receptor occupancy was determined in parallel using 3H-raclopride as the radioligand. The PK/PD relationship was established by modelling the time-response and time-plasma concentration data. We found the order of dopamine D2 receptor occupancy required to suppress conditioned avoidance response behaviour according to EC50 measurements to be sertindole (+dehydrosertindole)=dehydrosertindole=paliperidone (the metabolite of risperidone)=haloperidol=olanzapine>risperidone>>clozapine. Overall, a good agreement was observed between the rat dopamine D2 receptor occupancy levels providing 50% response in the conditioned avoidance response test and the dopamine D2 receptor occupancy levels reported from responding schizophrenic patients treated with antipsychotics. Predictions of therapeutically effective steady-state levels for sertindole (+dehydrosertindole) and olanzapine were 3-4-fold too high whereas for haloperidol, clozapine and risperidone the predicted steady-state EC50 in conditioned avoidance responding rats correlated well with the therapeutically effective plasma levels observed in patients. Accordingly, the proposed PK/PD model may act as a guide for determining effective plasma concentrations of potential antipsychotics in the clinical setting and thereby accelerating the overall drug development process.

Topics: Administration, Oral; Animals; Antipsychotic Agents; Basal Ganglia; Behavior, Animal; Benzodiazepines; Binding, Competitive; Clozapine; Conditioning, Psychological; Dopamine Antagonists; Haloperidol; Imidazoles; Indoles; Injections, Subcutaneous; Male; Models, Biological; Olanzapine; Protein Binding; Raclopride; Rats; Rats, Wistar; Receptors, Dopamine D2; Reproducibility of Results; Risperidone

To evaluate in vitro and computationally model the effects of selected antipsychotic drugs on several ionic currents that contribute to changes in the action potential in cardiac tissue.. Fourteen antipsychotic drugs or metabolites were examined to determine whether QT interval prolongation could be accounted for by an effect on one or more myocardial ion channels [I(to), I(Na), I(sus), I(K1), and human ether-a-go-go related gene (hERG)]. Using the patch clamp technique, drug effects on these human cardiac currents were tested.. All molecules had little inhibitory effect on ion channels (blocking at concentrations >5 microM) other than hERG. A significant correlation was observed between the estimated hERG blockade and the increase in corrected QT for five of the antipsychotics. Molecular modeling identified hydrophobic features related to the interaction with hERG and correctly rank-ordered the test set molecules olanzapine and its metabolites. A network analysis of ligand and protein interactions around hERG using MetaCore (GeneGo Inc., St. Joseph, MI, USA) was used to visualize antipsychotics with affinity for this channel and their interactions with other proteins in this database.. The antipsychotics do not inhibit the ion channels I(to), I(Na), I(sus), I(K1) to any appreciable extent; however, blockade of hERG is a likely mechanism for the prolongation of the QT interval.

Topics: Action Potentials; Aged; Antipsychotic Agents; Benzodiazepines; Cell Line; Electrocardiography; Ether-A-Go-Go Potassium Channels; Humans; Imidazoles; In Vitro Techniques; Indoles; Ion Channels; Middle Aged; Molecular Structure; Myocytes, Cardiac; Neural Networks, Computer; Olanzapine; Potassium Channel Blockers; Potassium Channels, Inwardly Rectifying; Sodium Channels; Structure-Activity Relationship; Thioridazine; Transfection

Cognitive deficits in schizophrenia are associated with poor functional outcome, and may be further aggravated by treatment with antipsychotics. In the present study the acute and chronic (3 weeks of treatment) effects of clozapine, olanzapine, and sertindole on performance in the Morris water maze in rats was compared, using pharmacologically and/or clinically relevant dose regimens. An experimental design consisting of three trials/day over 3 days was used. Performance was expressed as the distance and latency to find a submerged platform, as well as the percentage of "non-finders", i.e. percentage of trials where the rat was unable to find the platform within the total trial time of 60 s. Clozapine (40 mg/kg, p.o.) and olanzapine (2.5 mg/kg, s.c.) impaired water maze performance when given acutely. However, tolerance developed to the deficit induced by clozapine, whereas the olanzapine-mediated impairment was enhanced after chronic treatment. Sertindole (2.5 mg/kg, p.o.) had no disruptive effect on performance after either acute or chronic treatment. Exposure measurements confirmed that all three compounds were present in the serum at least at clinically effective concentrations. Thus, the three antipsychotics tested differentially affected rodent cognition, whereby sertindole appeared to have a lower potential than either clozapine or olanzapine to induce cognitive impairment. The hypothesis that the low potency of sertindole in inducing dopamine D2 receptor blockade, combined with lack of antimuscarinic and histamine H1 antagonist activity in vivo is discussed. Clearly further studies are needed to assess the potential cognition-enhancing effects of sertindole vs. other antipsychotics in a relevant animal model of schizophrenia.

Topics: Analysis of Variance; Animals; Antipsychotic Agents; Behavior, Animal; Benzodiazepines; Clozapine; Dose-Response Relationship, Drug; Imidazoles; Indoles; Male; Maze Learning; Olanzapine; Psychomotor Performance; Rats; Rats, Wistar; Time Factors

The current generation of atypical antipsychotic drugs represents an improvement over traditional ("typical") antipsychotics in many respects. However, a theoretical framework and adequate preclinical models have not yet been developed to predict or explain differences among the atypical antipsychotics, a necessary component of future development.. The purpose of the present set of experiments was to identify differences between the acute and subchronic effects of several atypical antipsychotic drugs and the typical antipsychotic haloperidol on operant responding in rats.. The effects of haloperidol and the atypical antipsychotics clozapine, olanzapine, risperidone, sertindole, quetiapine, remoxipride, and thioridazine were determined in rats trained to respond for food reward under a multiple fixed ratio 30/fixed interval 60 s schedule. A profile of the acute effects of each drug on response rates, response durations, and within-session effects were determined. Next, the dose of each drug that produced 75% suppression of response rates was administered for 16 consecutive days to determine whether or not tolerance would develop to the rate-suppressing effects of that dose.. All drugs produced dose-related decreases in response rates. Only haloperidol and risperidone produced significant increases in response duration, while only haloperidol and remoxipride displayed within-session response decrements. Tolerance was evident for clozapine and to a lesser extent thioridazine.. These results illustrate that the current generation of atypical antipsychotics are a heterogeneous group and that operant procedures may be useful for identifying differences preclinically. Specifically, clozapine appears to possess properties that distinguish it from other atypical antipsychotics, particularly after repeated dosing.

Topics: Animals; Antipsychotic Agents; Benzodiazepines; Clozapine; Conditioning, Operant; Dibenzothiazepines; Dose-Response Relationship, Drug; Haloperidol; Imidazoles; Indoles; Male; Olanzapine; Pirenzepine; Quetiapine Fumarate; Rats; Rats, Sprague-Dawley; Remoxipride; Risperidone; Thioridazine; Time Factors

The effects of three chronically administered antipsychotic drugs on selected neurochemical markers of dopaminergic and GABAergic transmission were compared within the cerebral regions making up the basal ganglia-thalamocortical parallel processing neuronal pathways. All three drugs reduce psychosis in humans, whereas only haloperidol, but not olanzapine or sertindole, induce purposeless oral chewing movements (CMs) in rats or cause high rates of parkinsonism or tardive dyskinesia in humans. Male Sprague Dawley rats were treated with haloperidol, sertindole, or olanzapine delivered in drinking water for 6 months at doses which produce drug plasma levels in rat in the human therapeutic range. Results show the expected dopamine D2 receptor upregulation in striatum predominantly with haloperidol, although mild D2 upregulation was apparent in striatum after olanzapine. GAD67 mRNA was increased in striatum and decreased in globus pallidus by haloperidol and sertindole, but not by olanzapine. In the substantia nigra pars reticulata (SNR), both olanzapine and sertindole failed to induce GABA(A) receptor upregulation or D1 receptor downregulation, but haloperidol did both, confirming a previous report. In thalamus, all three drugs increased GAD expression in the reticular nucleus, whereas only haloperidol decreased GABA(A) binding in the mediodorsal nucleus, actions consistent with a reduction in nigrothalamic, GABA-mediated neural transmission. These results are consistent with the idea that the two new antipsychotics tested have mild and regionally restricted actions within the basal ganglia nuclei and a common action on increasing GAD expression in the reticular nucleus of the thalamus (RtN). Haloperidol, in contrast, has a broad and potent action in basal ganglia, causing changes in SNR and in the mediodorsal nucleus, while also altering GAD mRNA in RtN, potentially reflective of its dyskinetic and antipsychotic actions.

Topics: Animals; Antipsychotic Agents; Benzodiazepines; Brain; Corpus Striatum; Down-Regulation; Haloperidol; Imidazoles; Indoles; Male; Neurotransmitter Agents; Olanzapine; Pirenzepine; Rats; Rats, Sprague-Dawley; Receptors, Dopamine D1; Receptors, Dopamine D2; Thalamus; Up-Regulation

Sertindole (Serdolect), an atypical antipsychotic, was voluntarily suspended in the European Union in 1998 following regulatory concerns over reports of serious cardiac dysrhythmias and sudden unexpected deaths. The reported causes of death, their frequency, prolongation of the rate corrected QT interval (QTc) and cardiac dysrhythmias in patients prescribed sertindole were compared with those for patients treated with two other atypical antipsychotics. All patients in England, prescribed atypical antipsychotics by general practitioners during each drug's immediate post-marketing period, were identified using an observational cohort technique, prescription-event monitoring. Mortality rates in the sertindole cohort were compared with those in a comparator cohort using standardized mortality ratios and incidence rate ratios. Cardiovascular events were reviewed and followed up to identify cases of prolongation of QTc interval. There was no statistically significant difference in mortality rates between sertindole and the comparator cohort, although confidence intervals (CI) were wide due to small numbers in the sertindole cohort. A much smaller number of patients were prescribed sertindole than the other antipsychotics. Six cases of prolongation of QTc interval were identified in 462 patients (1.3%, 95% CI 0.5-2.8) treated with sertindole and one with unspecified electrocardiogram changes in the comparator cohort of 16,542 patients. This study contributes to the understanding of the occurrence of prolongation of QTc interval during clinical use of sertindole, the incidence of which was similar to that in clinical trials. Although no statistically significant difference was shown in mortality rates between sertindole and comparator cohort, the sertindole cohort was too small to rule out an association between the use of this drug and cardiovascular deaths.

Topics: Adult; Aged; Aged, 80 and over; Antipsychotic Agents; Arrhythmias, Cardiac; Benzodiazepines; Cohort Studies; Death, Sudden; Electrocardiography; European Union; Female; Humans; Imidazoles; Indoles; Long QT Syndrome; Male; Middle Aged; Olanzapine; Pirenzepine; Product Surveillance, Postmarketing; Risperidone; Sex Factors

Dopamine (DA) receptor agonists disrupt the prepulse inhibition (PPI) in rats which is considered to model PPI deficits observed in schizophrenic patients. Many laboratories have demonstrated that both "typical" and "atypical" antipsychotics reverse the disruptive effect of DA agonists on PPI in rats. These results are based on acute treatment with antipsychotics, which is different from clinical observations since humans receive treatment for months and the effects of antipsychotics only emerge after weeks of treatment.. We aimed to investigate the effect of chronic treatment with "typical" and "atypical" antipsychotics on the PPI model in rats.. We investigated the effect of acute versus sub-chronic (3 days) and chronic (21 days) treatment with haloperidol or two "atypical" antipsychotics (olanzapine; sertindole) on d-amphetamine-disrupted PPI in rats.. We observed that all three antipsychotics dose-dependently reversed the disruptive effect of d-amphetamine after acute or sub-chronic treatment, but that this reversal effect disappeared after chronic treatment. We confirmed this effect in the same model using oral administration instead of mini-pumps, and in an additional model predictive of antipsychotic action, i.e. d-amphetamine-induced hyperactivity in rats.. The d-amphetamine-disrupted PPI model highlighted a modification in the effects of antipsychotics after chronic treatment when compared to their acute effects, but only the acute treatment can be considered predictive of antipsychotic action in clinic.

Topics: Acoustic Stimulation; Animals; Antipsychotic Agents; Benzodiazepines; Central Nervous System Stimulants; Dextroamphetamine; Haloperidol; Hyperkinesis; Imidazoles; Indoles; Male; Olanzapine; Pirenzepine; Rats; Rats, Wistar; Receptors, Dopamine; Reflex, Startle; Time Factors

Previous drug discrimination studies with clozapine have not reliably distinguished between atypical and typical antipsychotics.. The present study was conducted to determine whether low-dose clozapine drug discrimination could distinguish atypical from typical antipsychotics.. Rats were trained to discriminate 1.25 mg/kg clozapine from vehicle in a two-lever drug discrimination procedure.. Generalization testing revealed full substitution with the atypical antipsychotics olanzapine (90.3% maximum generalization), sertindole (99.8%), and risperidone (87.1%) and partial substitution for quetiapine (seroquel, 66.4%) and the typical antipsychotics haloperidol (56.8%) and thioridazine (74.3%). Remoxipride (23.1%) and the typical antipsychotics chlorpromazine (27.9%) and fluphenazine (29.5%) did not reliably substitute for clozapine.. In contrast to previous clozapine drug discrimination studies with higher training doses, the atypical antipsychotics olanzapine, sertindole, and risperidone reliably substituted for clozapine while typical antipsychotics did not. These results suggest that low-dose clozapine drug discrimination may be a more sensitive assay for distinguishing atypical from typical antipsychotic drugs.

Topics: Animals; Antipsychotic Agents; Benzodiazepines; Clozapine; Discrimination Learning; Imidazoles; Indoles; Male; Olanzapine; Pirenzepine; Rats; Rats, Sprague-Dawley; Risperidone

The effects of acute intravenous administration of several new, atypical antipsychotic drugs (APDs): olanzapine (0.05 and 1.0 mg/kg), sertindole (0.1 and 1.0 mg/kg) and quetiapine (0.25 and 2.5 mg/kg), a selective 5-HT(2A) receptor antagonist, M100907 (0.03 and 0.3 mg/kg), and an alpha(1)-adrenoceptor antagonist, prazosin (0.3 mg/kg), on regional dopamine output were examined in the two subdivisions of the nucleus accumbens (NAC), the core and shell, which seem associated with motor control and limbic functions, respectively, by using in vivo differential normal pulse voltammetry in anaesthetised, pargyline-pretreated rats. Both quetiapine and sertindole, in the two doses used, caused a more pronounced dopamine release in the shell than in the core region of the NAC. In contrast, the low dose of olanzapine increased dopamine output almost to the same extent in both regions, whereas the high dose increased dopamine output to a greater extent in the core. M100907 selectively increased dopamine output in the shell. Also, prazosin significantly increased dopamine output in the shell, but not in the core. The results indicate that both 5-HT(2A) and alpha(1)-adrenoceptor antagonism may play an important role in the preferential effect of atypical APDs on dopamine output in the shell versus the core of the NAC.

Topics: Adrenergic Antagonists; Animals; Antipsychotic Agents; Benzodiazepines; Dibenzothiazepines; Dopamine; Fluorobenzenes; Imidazoles; Indoles; Male; Nucleus Accumbens; Olanzapine; Piperidines; Pirenzepine; Quetiapine Fumarate; Rats; Rats, Sprague-Dawley; Receptor, Serotonin, 5-HT2A; Receptors, Adrenergic, alpha-1; Receptors, Serotonin; Serotonin Antagonists

Previous work suggests clozapine preferentially targets limbic cortical dopamine systems, which could help account for its lack of extrapyramidal side effects (EPS) and superior therapeutic efficacy.. To test the hypothesis that olanzapine, a novel atypical antipsychotic drug, occupies temporal cortical D2/D3 receptors to a greater extent than striatal D2/D3 receptors in vivo.. Nine schizophrenic patients taking either olanzapine [(n=5; mean (SD) age: 32.5 (6.5) years; daily dose: 18.3 (2.6) mg] or sertindole [(n=4; mean (SD) age: 30.3 (7.4) years; daily dose: 16 (5.6) mg] were studied with [123I]epidepride ((S)-N-[(1-ethyl-2-pyrrolidinyl)methyl]-5-iodo-2,3-dimethoxybenz amide) and single photon emission tomography (SPET). An estimate of [123I]epidepride 'specific binding' to D2/D3 receptors was obtained in patients and age-matched healthy volunteers. A summary measure was generated representing striatal and temporal cortical relative %D2/D3 receptor occupancy by antipsychotic drugs. Occupancy data were compared with previously studied groups of patients receiving typical antipsychotic drugs (n=12) and clozapine (n=10).. Mean striatal and temporal cortical %D2/D3 receptor occupancy in olanzapine-treated patients was 41.3% (SD 17.9) and 82.8% (SD 4.2), respectively. Unexpectedly low levels of striatal relative %D2/D3 receptor occupancy were seen in two patients with typical antipsychotic-drug-induced movement disorder prior to switching to olanzapine. In the temporal cortex, mean D2/D3 dopamine receptor occupancy levels above 80% were seen for all antipsychotic drugs studied.. The atypical antipsychotic drugs olanzapine and sertindole, in common with clozapine, demonstrate higher occupancy of temporal cortical than striatal D2/D3 dopamine receptors in vivo at clinically useful doses. This could help mediate their atypical clinical profile of therapeutic efficacy with few extrapyramidal side effects. Limbic selective blockade of D2/D3 dopamine receptors could be a common action of atypical antipsychotic drugs.

Topics: Adult; Analysis of Variance; Antipsychotic Agents; Benzamides; Benzodiazepines; Corpus Striatum; Female; Humans; Imidazoles; Indoles; Iodine Radioisotopes; Male; Middle Aged; Olanzapine; Pirenzepine; Pyrrolidines; Receptors, Dopamine D2; Receptors, Dopamine D3; Schizophrenia; Temporal Lobe; Tomography, Emission-Computed

The effect of the selective dopamine D2 receptor agonist quinpirole, the selective 5-HT1A receptor agonist 8-OH-DPAT and the selective 5-HT2A receptor antagonist ketanserin on catalepsy induced by atypical antipsychotics clozapine, risperidone, olanzapine and sertindole at higher doses was studied in rats. Haloperidol (0.5, 1 and 2 mg/kg), clozapine (50 and 75 mg/kg) and olanzapine (15 and 30 mg/kg) produced catalepsy dose-dependently while sertindole at doses up to 40 mg/kg failed to produce catalepsy in rats. However, sertindole (15, 30 and 45 mg/kg) produced a cataleptic effect in mice in a dose-dependent manner. At a high dose (5 mg/kg), risperidone produced catalepsy in rats. Quinpirole (0.05 and 0.1 mg/kg) reversed the cataleptic effect of haloperidol (2 mg/kg), risperidone (5 mg/kg), olanzapine (30 mg/kg) and sertindole (45 mg/kg). Quinpirole (0.05 and 0.1 mg/kg) reversed clozapine (75 mg/kg)-induced catalepsy. 8-OH-DPAT (0.15 and 0.3 mg/kg) dose-dependently reversed catalepsy induced by haloperidol (2 mg/kg) and risperidone (5 mg/kg) without affecting the cataleptic effect of olanzapine. However, the higher dose (0.45 mg/kg) of 8-OH-DPAT reversed it significantly. 8-OH-DPAT (0.3 mg/kg) reversed clozapine (75 mg/kg)-induced catalepsy. 8-OH-DPAT (0.15, 0.3 and 0.45 mg/kg) failed to reverse sertindole-induced catalepsy. Ketanserin (0.75 and 1.5 mg/kg) completely reversed catalepsy induced by haloperidol (2 mg/kg) and risperidone (5 mg/kg). Ketanserin (0.75 and 1.5 mg/kg) dose-dependently reversed olanzapine (30 mg/kg) and sertindole (45 mg/kg)-induced catalepsy without any effect on clozapine (75 mg/kg)-induced catalepsy. A higher dose (3 mg/kg) of ketanserin reversed clozapine-induced catalepsy. The present study suggests that atypical antipsychotics show fewer extrapyramidal symptoms (EPS) due to greater modulation of the serotonergic system. Therefore, an antipsychotic with dopamine D2/5-HT2A antagonistic action and 5-HT1A agonistic action may prove to be superior to the existing antipsychotics.

Topics: 8-Hydroxy-2-(di-n-propylamino)tetralin; Animals; Antipsychotic Agents; Benzodiazepines; Catalepsy; Clozapine; Dopamine Agonists; Dose-Response Relationship, Drug; Drug Interactions; Imidazoles; Indoles; Ketanserin; Male; Mice; Mice, Inbred BALB C; Olanzapine; Pirenzepine; Quinpirole; Random Allocation; Rats; Rats, Wistar; Risperidone; Serotonin Agents; Serotonin Antagonists; Serotonin Receptor Agonists; Species Specificity

Chronic haloperidol treatment typically produces late-onset, purposeless oral chewing movements in laboratory rats with a prevalence of 40 to 60%. Chronic clozapine does not produce these movements. Based on the phenomenologic and pharmacologic similarities between these rat chewing movements and human tardive dyskinesia (TD), the animal movements are often used as a model of tardive dyskinesia (TD). Here we report results of the association of oral chewing movements in rats with chronic administration of two new antipsychotic drugs, olanzapine and sertindole. Because each of these antipsychotic drugs has a very low incidence of acute Parkinsonism in human studies, they are candidates for showing a low tardive dyskinesia risk. Neither new drug produced a significant incidence of haloperidol-like chewing in rats, nor did movement ratings after their chronic administration differ from placebo; whereas, haloperidol produced a 60% prevalence of purposeless chewing and a prevalence significantly increased from placebo. This low rate of oral dyskinesias in rats is consistent with several of the preclinical characteristics of the drugs and correlates with their low acute motor side effects in clinical trials. We propose, although have not yet tested in humans, that these animal results will predict low TD liability of these drugs.

Topics: Animals; Antipsychotic Agents; Benzodiazepines; Dyskinesia, Drug-Induced; Haloperidol; Imidazoles; Indoles; Male; Mastication; Olanzapine; Pirenzepine; Rats; Rats, Sprague-Dawley

In a previous study using Sprague-Dawley rats, we showed that in a prepulse inhibition (PPI) procedure with levels of PPI ranging from approximately 10 to 40% (for prepulse intensities 2, 9 and 15 dB above background noise), the antipsychotics clozapine and haloperidol, but also the alpha 1 adrenoceptor antagonist prazosin, robustly and dose-dependently potentiated PPI. In contrast, the antipsychotics risperidone, amisulpride, raclopride and remoxipride did not potentiate PPI. The false positive (prazosin) and the four false negatives led us to conclude that this PPI-enhancing procedure had poor predictive validity as a screening tool for potential antipsychotics. In the present study, we used Wistar rats, which under the same protocol as that used for Sprague-Dawley rats show a very low level of PPI. We examined the ability of six antipsychotics, given intraperitoneally (i.p.), to reverse this PPI deficit. It was found that clozapine (5-20 mg/kg), olanzapine (5-20 mg/kg) and sertindole (1-10 mg/kg) reversed this deficiency of PPI (i.e. potentiated the low level of PPI). In contrast, risperidone (0.1-1 mg/kg), remoxipride (1-10 mg/kg) and haloperidol (0.1-1 mg/kg) were inactive. The negative results with three clinically active antipsychotics (risperidone, remoxipride and haloperidol) indicate that reversal of this PPI deficit in Wistar rats has poor predictive validity to screen for potential antipsychotic activity. In an attempt to investigate the mechanism that might underlie the reversing effect of clozapine, olanzapine and sertindole, we tested the ability of the alpha 1 adrenoceptor antagonist prazosin (3-20 mg/kg), the dopamine D1 receptor antagonist SCH 23390 (0.01-0.1 mg/kg) and the 5-HT2 antagonist ritanserin (0.3-3 mg/kg) to reverse the PPI deficit. Negative results with these three drugs did not allow us to characterize the receptor(s) that might be implicated in the reversal of this type of PPI deficit.

Topics: Adrenergic alpha-Antagonists; Animals; Antipsychotic Agents; Behavior, Animal; Benzazepines; Benzodiazepines; Clozapine; Haloperidol; Imidazoles; Indoles; Injections, Intraperitoneal; Male; Neural Inhibition; Olanzapine; Pirenzepine; Prazosin; Rats; Rats, Wistar; Reflex, Startle; Remoxipride; Risperidone; Ritanserin; Serotonin Antagonists

Phencyclidine (PCP) induces stereotyped behaviour and social isolation in rats; comparisons with clinical observations have suggested that these behaviours may mimic certain aspects of the positive and the negative symptoms, respectively, of an acute schizophrenic episode. Novel antipsychotics are effective in treating the positive symptoms in schizophrenic patients and have also shown some promise in treating the negative symptoms. In the present study the effects of the novel antipsychotics remoxipride (2.5-20 mg/kg), risperidone (0.02-0.63 mg/kg), sertindole (0.01-2.5 mg/kg), olanzapine (0.16-2.5 mg/kg) and quetiapine (0.16-10 mg/kg) on PCP-induced behaviours were determined. The drugs were administered daily for 3 or 21 days in combination with vehicle or 2.0 mg/kg of PCP for the last 3 days of the administration regime, and the rats were tested using the social interaction test. The antipsychotic drugs all reliably reduced the level of PCP-induced stereotyped behaviour and had distinct effects on PCP-induced social isolation. Comparison with clinical findings suggests that the PCP-induced behaviours respond to treatment with antipsychotic drugs in a manner that correlates well with clinical observations, and that this animal model of schizophrenia may be useful for evaluating novel drug candidates. However, the study also showed that additional experiments are required to determine the specificity by which antipsychotic drugs alleviate PCP-induced behaviours because most of the drugs also affected considerably the behaviour of the control animals.

Topics: Animals; Antipsychotic Agents; Avoidance Learning; Benzodiazepines; Dibenzothiazepines; Dose-Response Relationship, Drug; Hallucinogens; Imidazoles; Indoles; Interpersonal Relations; Male; Olanzapine; Phencyclidine; Pirenzepine; Quetiapine Fumarate; Rats; Rats, Wistar; Remoxipride; Social Isolation; Stereotypic Movement Disorder

The paw test was used to detect the preclinical profile (classical versus atypical) of five putative, atypical neuroleptics, namely olanzapine, sertindole, risperidone, prothipendyl and ORG 5222. In the paw test classical neuroleptics increase the hindlimb reaction time (HRT), a parameter with predictive validity for antipsychotic efficacy, at doses comparable to those necessary for increasing forelimb reaction time (FRT), a parameter with predictive validity for extrapyramidal side-effects, whereas atypical neuroleptics increase HRT at doses that are much smaller than those increasing FRT. All tested compounds showed the profile of atypical neuroleptics in the paw test. Using the FRT/HRT ratio of minimum effective doses as overall predictor of a favourable ratio of extrapyramidal and therapeutic effects of these drugs, the following order was found: olanzapine (20) > sertindole = risperidone = prothipendyl (10) > ORG 5222 (3). The ability of compounds to attenuate locomotor activity elicited either from the olfactory tubercle (10 micrograms dopamine: OT test) or from the nucleus accumbens (1 microgram ergometrine: ACC test) was used to establish whether the compounds preferentially act in one of these structures. Previous research has shown that classical neuroleptics are far less potent in the OT test than in the ACC test, whereas atypical neuroleptics are far more potent in the OT test than in the ACC test. All five agents preferentially acted in the olfactory tubercle. The order of potency in the olfactory tubercle was as follows: sertindole > ORG 5222 > risperidone > olanzapine > prothipendyl. It is concluded that risperidone, prothipendyl, ORG 5222, sertindole and olanzapine not only show the profile of atypical neuroleptics in the paw test, but also preferentially act in the olfactory tubercle, but not in the nucleus accumbens, viz. two features that they share with the atypical neuroleptics clozapine and thioridazine and with the putative, atypical neuroleptics raclopride and remoxipride.

Topics: Animals; Anti-Anxiety Agents; Antipsychotic Agents; Benzodiazepines; Dibenzocycloheptenes; Dibenzoxepins; Dose-Response Relationship, Drug; Heterocyclic Compounds, 4 or More Rings; Imidazoles; Indoles; Locomotion; Male; Olanzapine; Olfactory Pathways; Pirenzepine; Rats; Rats, Wistar; Risperidone; Thiazines; Time Factors