Olanzapine and clozapine
Top Cited Papers
- 26 September 2000
- journal article
- clinical trial
- Published by Wolters Kluwer Health in Neurology
- Vol. 55 (6) , 789-794
- https://doi.org/10.1212/wnl.55.6.789
Abstract
Objective: To compare olanzapine and clozapine for safety and efficacy measures of psychosis and motor function in patients with PD and chronic hallucinations. Background: Hallucinations occur in approximately one third of patients with PD treated chronically with dopaminergic drugs. Although clozapine is known to be an effective antipsychotic agent that does not significantly exacerbate parkinsonism, its use requires frequent blood count assessment. Olanzapine is another novel antipsychotic that is not associated with blood dyscrasia, and if equally effective could become the preferred drug for treating hallucinations in subjects with PD. Methods: A randomized, double-blind, parallel comparison of olanzapine and clozapine in patients with PD with chronic hallucinations was conducted. The primary outcome measure was the Scale for the Assessment of Positive Symptoms (SAPS) for psychotic symptoms. The Unified Parkinson’s Disease Rating Scale (UPDRS) motor subscale was used as a secondary outcome measure and as a safety monitoring tool. Results: After 15 patients had completed the study, safety stopping rules were invoked because of exacerbated parkinsonism in olanzapine-treated subjects. UPDRS motor impairment scores from baseline to study end significantly increased with olanzapine treatment, and change scores between the olanzapine and clozapine groups significantly differed. The primary clinical domains responsible for the motor decline were gait and bradykinesia. Even with a smaller patient number than originally anticipated, clozapine significantly improved hallucinations and overall behavioral assessment, whereas olanzapine had no effect. Conclusions: At the doses studied, olanzapine aggravates parkinsonism in comparison with clozapine and should not be regularly used in the management of hallucinations in patients with PD.Keywords
This publication has 17 references indexed in Scilit:
- Low-Dose Clozapine for the Treatment of Drug-Induced Psychosis in Parkinson's DiseaseNew England Journal of Medicine, 1999
- Factor structure and clinical validity of competing models of positive symptoms in schizophreniaBiological Psychiatry, 1998
- Visual Hallucinations Associated With Parkinson DiseaseArchives of Neurology, 1996
- Olanzapine in the treatment of dopaminomimetic psychosis in patients with Parkinson's diseaseNeurology, 1996
- Psychosis in advanced Parkinson's diseaseNeurology, 1995
- Mortality and hallucinations in nursing home patients with advanced Parkinson's diseaseNeurology, 1995
- Risk factors for nursing home placement in advanced Parkinson's diseaseNeurology, 1993
- ClozapineNew England Journal of Medicine, 1991
- Clozapine‐responsive tremor in Parkinson's diseaseMovement Disorders, 1990
- Nucleus ruber and L-Dopa psychosis: Biochemical post-mortem findingsJournal Of Neural Transmission-Parkinsons Disease and Dementia Section, 1974