Psychosis occurs in PD is very common and may also occur in the setting of infection. psychosis has been one of the most common causes of hospitalization of PD patients and may be secondary to PD medications.
Withdraw medications in this order: anticholinergic medications>MAOBinhibitors>dopamine agonists>COMTinhibitors>minimize levodopa dose
Miyasaki JM, Shannon K, Voon V, et al; Quality Standards Subcommittee of the American Academy of Neurology. Practice Parameter: evaluation and treatment of depression, psychosis, and dementia in Parkinson disease (an evidence-based review): report of the Quality Standards Subcommittee of the American Academy of Neurology. Neurology. 2006;66(7):996-1002.