Psychotic symptoms are the most important non-motoric symptoms of the Parkinson disease (PD). The quality of life of those patients can be significantly improved with an appropriate therapy. In this article we provide evidence about the etiology, differential diagnosis and therapeutic possibilities with a work-up for the clinics.

To provide a case report of patient with PD who developed a paranoid psychosis after administration of levodopa/carbidopa, followed by a literature review on psychotic symptoms evoked by psychotropic medication by patients with PD.

An English-language literature search was conducted using Pubmed, EMBASE searching for case reports and observational studies reporting iatrogenic psychotic symptoms by patients with PD.

Ms. C. was a 65-year old woman with PD who was observed in a polyclinic setting and who used a levodopa/carbidopa combination. She developed paranoid psychosis with a following admission to the psychiatric ward. We have gradually lowered the dose of anti-Parkinson medication. Subsequently, treatment with clozapine was initiated and the psychotic symptoms resolved within five months.

Parkinson psychosis is due to a complex interaction of neurodegenerative changes and pharmacological therapy. Therefore, the role of iatrogenic factors must be always carefully assessed. Psychosis inducting agents should be lowered or stopped before the treatment with antipsychotic medication.

The authors have not supplied their declaration of competing interest.