[Hallucinations and Parkinson's disease in the elderly: Pitfalls and medical care]

Hallucinations are common neuropsychiatric symptoms in Parkinson's disease (PD), with a significant prognosis impact. It is necessary to rule out other diagnoses that can be mentioned when hallucinations occur in old patients with PD. The various etiological factors must be systematically checked and can help for diagnosis. Medical care will be focused on treating the primary cause (medical or iatrogenic origin) and will privilege non-pharmacological strategies. Due to their frequent adverse effects, antipsychotic medication should be limited and started at low dose in old patients with multiple comorbidities. Clozapine and quetiapine have the highest level of recommendation in this indication. In the future, defining fMRI-based targets for noninvasive brain stimulation tools should pave the way for innovative non-pharmacological treatment of hallucinations.