Low-dose olanzapine for levodopa induced dyskinesias.
OBJECTIVE
To assess the usefulness of low-dose olanzapine (2.5 to 7. 5 mg/day) for Levodopa-induced-dyskinesias (LID) in patients with PD.


METHODS
Ten patients with PD and LID took part in this randomized, placebo-controlled, double blind, crossover trial. Patients received a 2-week course of olanzapine or placebo in each treatment phase with 1-week washout in between. Dyskinesias were assessed at baseline and after each treatment period with an acute dopaminergic challenge and unified PD rating scale (UPDRS) questionnaires. Patients also kept on/off and dyskinesia diaries for the last 3 days prior to each assessment.


RESULTS
There was a 41% difference in dyskinesia reduction on olanzapine compared to placebo, as measured by objective dyskinesia rating scales (mean percentage reduction abnormal involuntary movement score: 30% versus -11.2%, p < 0.02). Similar differences were demonstrated by patient diaries (mean reduction: 46% versus -2%, p < 0.02) and UPDRS items 32 and 33. Compared with placebo, treatment with olanzapine resulted in significant increases in 'off' time as measured by patient diaries (30% versus 2%) and reported adverse events (1.7 versus 0.1) including increased parkinsonism (1.1 versus 0.1) and a nonsignificant reported increase in drowsiness.


CONCLUSIONS
Low-dose olanzapine is effective in reducing dyskinesias in PD, but even at very low doses can result in unacceptable increases in parkinsonism and 'off' time.
Manson
A J
AJ
National Hospital for Neurology and Neurosurgery, Queen Square, London, UK.
Schrag
A
A
Lees
A J
AJ
D000368:Aged; D001569:Benzodiazepines; D004311:Double-Blind Method; D004409:Dyskinesia, Drug-Induced / Q000188:drug therapy* / Q000503:physiopathology; D005260:Female; D006801:Humans; D007980:Levodopa / Q000009:adverse effects*; D008297:Male; D008875:Middle Aged; D000077152:Olanzapine; D010890:Pirenzepine / Q000008:administration & dosage* / Q000009:adverse effects / Q000031:analogs & derivatives*
D001569:Benzodiazepines; D010890:Pirenzepine; D007980:Levodopa; D000077152:Olanzapine