olanzapine and Hypotension--Orthostatic

Behavioral and psychological symptoms of dementia pose management challenges for caregivers and clinicians. Firstline nonpharmacologic treatments include eliminating physical and emotional stressors, modifying the patient's environment, and establishing daily routines. Family members and caregivers benefit from education about dementia symptoms and reminders that the behaviors are normal and unintentional. Cognitive and emotion-oriented interventions, sensory stimulation interventions, behavior management techniques, and other psychosocial interventions are modestly effective. In refractory cases, physicians may choose to prescribe off-label antipsychotics. Aripiprazole has the most consistent evidence of symptom improvement; however, this improvement is small. Olanzapine, quetiapine, and risperidone have inconsistent evidence of benefit. Physicians should use the smallest effective dose for the shortest possible duration to minimize adverse effects, most notably an increased mortality risk. Other adverse effects include anticholinergic and antidopaminergic effects, extrapyramidal symptoms, neuroleptic malignant syndrome, postural hypotension, metabolic syndrome, cardiac arrhythmia, and sedation. Patients should be monitored for these effects while receiving treatment; however, laboratory monitoring may be limited to patients receiving long-term therapy.

Topics: Antipsychotic Agents; Aripiprazole; Arrhythmias, Cardiac; Basal Ganglia Diseases; Behavior Therapy; Benzodiazepines; Cognitive Behavioral Therapy; Dementia; Emotions; Humans; Hypotension, Orthostatic; Metabolic Syndrome; Neuroleptic Malignant Syndrome; Olanzapine; Practice Guidelines as Topic; Psychotic Disorders; Quetiapine Fumarate; Risperidone

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

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

Topics: Antipsychotic Agents; Benzodiazepines; Constipation; Costs and Cost Analysis; Dizziness; Dose-Response Relationship, Drug; Double-Blind Method; Drug Therapy; Humans; Hypotension, Orthostatic; Olanzapine; Pirenzepine; Schizophrenia; Sleep; Weight Gain

Olanzapine is an "atypical" antipsychotic agent with a high affinity for serotonin 5HT2A/C, 5HT3, 5HT6, and dopamine D1, D2, D3, D4 receptors. Depressed patients with psychotic disorders frequently require treatment with concomitant antipsychotic and antidepressant medications. Imipramine pharmacokinetics serve as a marker for hepatic CYP2D6, CYP1A2, CYP3A activity. An open-label, three-way randomized crossover study was done to determine the safety, pharmacokinetics, and potential for a drug interaction between olanzapine (5 mg) and imipramine (75 mg). Each drug was administered alone and in combination. Nine healthy men, ages 32 to 54 years, enrolled in the study. Psychomotor performance capacities, plasma olanzapine, imipramine, desipramine concentrations, and clinical laboratory tests were measured. Pharmacokinetic variables, vital signs, subjective tests for liveliness, and psychomotor outcomes were analyzed using a two-way ANOVA. Olanzapine was safe. Sedation, postural hypotension, and minor vital sign alterations occurred during all treatments. On the liveliness questionnaire, patients generally reported poorer (less lively) scores with olanzapine alone or coadministered with imipramine versus baseline scores. These effects disappeared within 24 hours after administration. Olanzapine alone and in combination decreased motor-speed tasks (finger tapping and visual-arm random reach) compared with baseline or imipramine treatment. Peak 6-hour changes were statistically significant but clinical importance was only marginal. Olanzapine concentrations were < 19% greater than with imipramine. But olanzapine did not affect the kinetics of imipramine or desipramine and, therefore, did not show a metabolic drug interaction involving CYP2D6.

Topics: Adrenergic Uptake Inhibitors; Adult; Analysis of Variance; Antipsychotic Agents; Benzodiazepines; Cross-Over Studies; Drug Interactions; Humans; Hypotension, Orthostatic; Imipramine; Male; Middle Aged; Olanzapine; Pirenzepine; Psychomotor Performance; Single-Blind Method

Many antipsychotics cause orthostatic hypotension possibly due to antagonist action on resistance vessel alpha1A-adrenoceptors (alpha1A-AR).. We have tested this possibility by determining in Wistar rats how the orthostatic hypotensive effect of several antipsychotic drugs compares with their affinity for adrenoceptors in mesenteric small arteries (MSA with mainly alpha1A-AR) and aorta (mainly alpha1D-AR).. Using a tilt setup, orthostatic hypotension was measured in anaesthetized rats for prazosin and the antipsychotics haloperidol, sertindole, risperidone, clozapine, ziprasidone, domperidone, olanzapine, and aripiprazole. For in vitro studies, segments of MSA and aorta were mounted on a wire myograph for isometric tension recording. Cumulative concentration-response curves were constructed to phenylephrine (PE) in the absence and presence of the drugs. Apparent affinity (pA2) was calculated by Schild analysis.. Prazosin antagonized tilt-induced and PE responses in both studies (threshold 4 ng/ml, pA2 9.52 MSA, 10.1 aorta). The rank order of the potency of the antipsychotics in the tilt experiments correlated (r2 = 0.69, P = 0.01) with the pA2-values in MSA: Risperidone and sertindole had the highest potency in the tilt test (threshold 159 and 97 ng/ml) and the highest apparent affinity in MSA (pA2 8.92 and 8.78), in contrast with aripiprazole and domperidone, which had the lowest in each case (threshold 4.1 and 3.0 microg/ml, pA2 7.17 and 6.99). In aorta, the pA2 values did not correlate with the in vivo potencies; in particular, sertindole had no functional affinity in aorta.. We conclude that the orthostatic hypotensive effect in rats of the antipsychotic drugs investigated is mediated through alpha1A-ARs.

Topics: Animals; Antipsychotic Agents; Aorta; Dose-Response Relationship, Drug; Hypotension, Orthostatic; In Vitro Techniques; Male; Mesenteric Arteries; Phenylephrine; Prazosin; Rats; Receptors, Adrenergic, alpha-1; Vasoconstriction