Clozapine Use in a Movement Disorder Clinic

Background: Clozapine is an effective antipsychotic for Parkinson's disease (PD) that does not worsen motor function and can improve tremor. It is approved for PD psychosis in Europe and Australia.

Objective: The aim of this study was to report on the use of clozapine in a movement disorder clinic.

Methods: We report on patients monitored during the COVID-19 pandemic in clinic over a 7-month period.

Results: Sixty-five patients were seen, of whom 50 had PD. Thirty-one were treated for psychosis, 18 for refractory tremor and 1 for levodopa dyskinesias. The remainder had psychotic symptoms with dementia with Lewy bodies (n = 2) or other movement disorders. Four had clozapine discontinued because of sedation and 1 for agranulocytosis. Three had clozapine temporarily halted because of granulocytopenia but were rechallenged successfully.

Conclusions: When comparing clozapine use in this clinic as compared with others, we deduce that clozapine is likely significantly underutilized in the United States.