Abstract
Introduction: Psychosis in Parkinson disease is a therapeutic challenge. Regular strategies of
treatment are aimed at reducing dopamine medication, and if necessary addition of
clozapine.
Methods: We describe the case of a patient with persistent psychosis. Nocturnal visual hallucinations
persisted in spite of reduced dopaminergic medication and sequential treatment with
atypical antipsychotic medication (quetiapine and clozapine) in combination with an
acetylcholinesterase inhibitor (rivastigmine). After dispensing a dopamine enhancing
antidepressant (mirtazapine), prescribed to improve sleeping, the psychotic symptoms
almost immediately disappeared while Parkinsons symptoms declined.
Results: One other case about a positive effect of mirtazapine on (auditory) hallucinations
in Parkinson has been published. The reason for the reduction of psychosis in Parkinson-related
disease could have been the effect of antagonism of serotonin (5HT)-2 A and/or antagonism
of 5HT-2C leading to dopamine release.
Discussion: Therapeutic effects of medication with strong antagonism for 5HT-2 A and 5HT-2C,
like mirtazapine, mianserine, trazodone and nefazodone, in Parkinson-related diseases
should be subject for further research. Serotonin might be associated with psychosis
in Parkinson-related disease.
Key words
psychosis - hallucinations - mirtazapine - SSRI - Parkinson’s disease - Lewy bodies
