Parkinson's psychosis.

OPINION STATEMENT: Psychosis is a leading reason for nursing home placement of patients with Parkinson's disease (PD). It may also be the single greatest stressor for caregivers of PD patients, it is generally persistent, and its presence markedly increases the risk of mortality. For these reasons, it is essential to recognize and appropriately treat psychosis in PD. Treatment of psychotic symptoms should be initiated after potential medical and environmental causes of delirium (eg, infection) have been eliminated or addressed. Initial pharmacologic changes should include limiting the patient's anti-PD medications to those that are necessary to preserve motor function (ie, eliminating adjunctive agents). Should that fail, an atypical antipsychotic agent is the treatment of choice. Clozapine is presently the gold standard, and quetiapine represents another option because of its ease of use and good tolerability profile. Emerging treatment options include the use of acetylcholinesterase inhibitors, antidepressants, and cognitive behavioral therapy. This article reviews what is currently known about treatment strategies in PD psychosis.