Amoxapine as an atypical antipsychotic: a comparative study vs risperidone.

Abstract

Amoxapine is marketed as an antidepressant. However, its in-vitro profile, receptor occupancy and preclinical effects are very similar to atypical antipsychotics. Amoxapine has also shown efficacy as an atypical antipsychotic in open trials. The objective of this study was to compare the antipsychotic and side effect profile of amoxapine and risperidone in a randomised assignment, standardized dosing, double-blind trial of acutely psychotic patients with schizophrenia. A total of 48 schizophrenic patients were enrolled and randomized in a double-blind 6-week trial to receive either risperidone (up to 5 mg/day) or amoxapine (up to 250 mg/day). Positive, negative, affective symptoms and motor side effects were measured using standardized weekly assessments. Prolactin levels were also determined at baseline and at the end of the study. A total of 39 patients (amoxapine, n=22; risperidone, n=21) completed the trial. Both pharmacological treatments, amoxapine 228.0 mg/day (SD=34.6) and risperidone 4.5 mg/day (SD=0.7), showed equivalent improvement in positive, negative, and depressive symptoms. Amoxapine was associated with less EPS and less prolactin elevation than risperidone. These data support previous reports about the efficacy of amoxapine as an atypical antipsychotic. Since amoxapine is off-patent, it may be a valuable low-cost alternative to new atypical antipsychotics, particularly in low-income countries where the majority of the patients are still treated with typical antipsychotics.

• Authors: Rogelio Apiquian, Ana Fresan, Rosa-Elena Ulloa, Camilo de la Fuente-Sandoval, Miguel Herrera-Estrella, Alejandra Vazquez, Humberto Nicolini, Shitij Kapur
• Journal: Neuropsychopharmacology : official publication of the American College of Neuropsychopharmacology (Neuropsychopharmacology) Vol. 30 Issue 12 Pg. 2236-44 (Dec 2005) ISSN: 0893-133X [Print] England
• PMID: 15956984 (Publication Type: Comparative Study, Journal Article, Randomized Controlled Trial, Research Support, Non-U.S. Gov't)

Chemical References

• Antipsychotic Agents
• Prolactin
• Risperidone
• Amoxapine

Topics

• Adolescent
• Adult
• Amoxapine (adverse effects, therapeutic use)
• Antipsychotic Agents (adverse effects, therapeutic use)
• Dose-Response Relationship, Drug
• Double-Blind Method
• Dyskinesia, Drug-Induced (drug therapy, epidemiology)
• Electrocardiography
• Female
• Humans
• Male
• Middle Aged
• Prolactin (blood)
• Psychotic Disorders (drug therapy)
• Risperidone (adverse effects, therapeutic use)
• Weight Gain (drug effects)