Pathological gambling in two patients on dopamine replacement therapy for Parkinson's disease.

We describe two cases where increases in dopaminergic therapy were initiated by the patients due to perceived deterioration in symptoms of idiopathic Parkinson's disease. Shortly afterwards, both cases also met clinical criteria for pathological gambling. To date, only 29 cases of pathological gambling in patients with Parkinson's disease have been reported. This "pathological gambling disorder" is an addiction-like behavior triggered by excessive dopaminergic drugs and does not respond to standard therapy for pathological gambling. It only responds to an adjustment of Parkinson's disease therapy.