Apomorphine therapy in Parkinson's and future directions.

Apomorphine infusion or injection is an important dopamine agonist non-oral therapy usually used in advanced Parkinson's disease (PD) with refractory motor fluctuations. The drug also has appreciable efficacy for nonmotor fluctuations and is the quickest to reverse predictable "off" periods. Current subcutaneous administration, however, is complicated by problems associated with needle-based therapies, such as skin nodule formation, skin irritation, and avoidance of this treatment option by needle-phobic subjects. In this review we focus on what the future might hold for apomorphine injection/infusion. We discuss interesting and novel delivery strategies of apomorphine or esters via oral, buccal, inhalation and a novel pump-patch route. We also discuss recent research that has highlighted some important properties of apomorphine in animal models, such as a potential anti-amyloid effect and its potential impact in the management of PD dementia or perhaps even Alzheimer's disease. A potential role for apomorphine infusion in cases with impulse control disorders and other nonmotor issues is also discussed.