Psychosis and antipsychotic medications in Alzheimer's disease: clinical management and research perspectives

Psychosis is common in patients with Alzheimer's disease (AD) and contributes substantially to patient morbidity and caregiver distress. Antipsychotic medications are used to treat psychosis and other psychiatric or behavioral symptoms in AD, although optimal treatment guidelines have been elusive. Choosing the most advantageous medication for an individual patient is challenging. This article provides an overview of clinical management principles and medication treatment strategies for patients with AD and psychosis. Effects of individual medications are also described. Medications in the conventional neuroleptic, atypical antipsychotic, cholinesterase inhibitor, and serotonergic classes have been shown to ameliorate psychosis and behavioral symptoms in patients with AD, although the evidence is not conclusive for many medications. Side effects vary substantially across medication classes and modestly among individual patients. Improvement in agitation, aggression, or other behaviors with antipsychotic medication treatment may not depend on distinct antipsychotic effects. In contrast, there is preliminary evidence that delusions and hallucinations may respond to treatment with medications outside the antipsychotic class. Many important clinical questions warrant further research study. In particular, studies to compare how individual symptoms respond to different medications, and to examine how to best manage overlapping symptoms or incomplete treatment response are needed.