Levodopa-induced psychosis can complicate the treatment of Parkinson's disease (PD). In
this retrospective, uncontrolled report, we describe our experience treating PD-related
psychosis with clozapine, emphasizing those patients treated for longer than 1 year. Twenty-
seven patients were treated, 14 for longer than 1 year. Most patients showed a rapid
improvement from baseline within 1 month using the Clinical Global Impression and Global
Psychosis Rating Scores. Five patients discontinued the drug due to side effects, but only …