Psychosis in Parkinson Disease

A host of neuropsychiatric disorders are intrinsic to Parkinson disease or occur as a complication of the dopaminergic therapies (dopamine agonists, levodopa) or anticholinergic medications used to treat the motor symptoms (Table 1). For some patients with PD, the neuropsychiatric complications are a greater source of morbidity than the motor dysfunction.[1,2] The neuropsychiatric disorders associated with dopaminergic therapies are important to recognize, because they are at least partially iatrogenic and can often be successfully managed by adjustment of the patient’s PD medications. We offer a detailed review in our article Management of Psychosis in Parkinson Disease.[3]

Dopamine agonists are more likely to provoke hallucinations than is carbidopa/levodopa. Psychosis with hallucinations and delusions has been reported in as many as 20% of nondemented patients who receive medications for PD (Table 2).[4,5]

The management of psychosis in PD with dementia is challenging (Table 3). In these patients, an attempt should be made to taper the use of combination therapy with dopamine agonists, anticholinergics, amantadine, MAO-B inhibitors, and COMT inhibitors.[6]