Management of psychosis in Parkinson's disease.

Psychosis is one of the most disabling complications associated with Parkinson's disease (PD) and occurs in up to 30% of PD patients treated chronically with antiparkinsonian drugs. Visual hallucinations, with or without delirium and paranoid delusions, are the most frequent symptoms. Psychosis complicating PD can be more disabling than the motor symptoms of PD; it frequently poses a serious threat to the patient's ability to maintain independence and is the single greatest risk factor for nursing home placement.