Dopamine dysregulation syndrome in Parkinson's disease patients with unsatisfactory switching from immediate to extended release pramipexole: a further clue to incentive sensitization mechanisms?

A small proportion of patients with Parkinson's disease (PD), chronically under dopamine replacement therapy, may undergo an addiction-like behavioral disturbance, named dopamine dysregulation syndrome (DDS). This behavioral disorder is characterized by the increase of doses beyond those required for motor control, and its management remains difficult; thus, early recognition and careful monitoring of at-risk individuals are crucial. We report the cases of two PD patients with a previous unsatisfactory switching from an immediate release (IR) to an extended release (ER) pramipexole formulation who developed DDS. PD patients unsatisfactorily switched from an IR to an ER formulation of dopamine agonists should be considered as at-risk individuals for DDS development.