Dyskinesias commonly appear during L-dihydroxyphenylalanine (L-DOPA) therapy of advanced Parkinson's disease (PD) and can occur in both dose-related and dose-independent patterns. Clozapine exerts a dose-related suppression of L-DOPA-induced dyskinesias by shifting the i.v. L-DOPA dose-response curve for production of dyskinesias without altering relief of parkinsonism. We report our outpatient experience with 13 patients on daily clozapine therapy (maximum dose 400 mg/day), followed for 3-21 months (median 10). Beneficial effects of clozapine, determined from twice-weekly diaries, included increased "on time" and decreased "off time" and time "on with dyskinesia." Improvements were statistically apparent by 75 mg/day and remained so through 200 mg/day. Sedation was a common problem, reflected by increased time "asleep" which was significant by 50 mg/day. Sedation was dose limiting in most patients. Orthostatic hypotension and sialorrhea were variably present. No patients had seizures, bone marrow toxicity, or detectable loss of efficacy of clozapine with chronic use. We conclude that clozapine is an effective agent for suppression of dyskinesias in PD with an effective daily dose for most patients of 100-200 mg/day.

The effects of stimulus rate and gender on the auditory middle latency response (AMLR) waveforms were examined in 20 young adult male and female subjects. Four different repetition rates were presented to subjects (1.1/sec, 4.1/sec, 7.7/sec, and 11.3/sec). Stimulus repetition rate had a significant effect on Pa latency, Pa amplitude, and Pb amplitude. Pa and Pb amplitudes decreased with increasing the stimulus rate, and Pa latency significantly increased with increasing the stimulus rate. No significant differences were seen on Pb latency or site of recording. Gender had a significant effect on Pa latency and Pa amplitude. Pa latencies were longer in male subjects, and Pa amplitudes were larger in female subjects. Gender did not have a significant effect on the Pb waveform.

No abstract

No abstract

No abstract