Continuous dopaminergic stimulation--from theory to clinical practice.

Patients with advanced Parkinson's disease (PD) experience worsening motor fluctuations and dyskinesia. Management options include deep brain stimulation of the subthalamic nucleus (STN-DBS), subcutaneous apomorphine (in combination with oral levodopa) or continuous duodenal levodopa administration. We have used all three therapies at our clinic in Milan and report our experience. Apomorphine infusion reduced daily off time but did not improve dyskinesia; long-term treatment was associated with impulse control disorders. STN-DBS provided motor benefit, but was associated with behavioural changes including attempted suicide. Duodenal levodopa produced significant clinical benefit without behavioural changes and allowed patients to discontinue all other PD medications. Duodenal levodopa should be considered in PD patients with advanced disease.