The role of apomorphine in the treatment of Parkinson's disease

Apomorphine (APO) is the oldest and most potent dopaminergic drug with multiple diagnostic and therapeutic uses in Parkinson's disease (PD). After subcutaneous administration, it has a very rapid and short duration effect. As a diagnostic test of dopaminergic responsiveness, the challenge with APO can also help the classification of dopaminergic-induced dyskinesias and response fluctuations. In advanced PD, intermittent injections of APO are an effective rescue treatment for off-state akinesia. In turn, continuous subcutaneous APO infusion with portable pump can effectively diminish motor state fluctuations and dyskinesias. Other administration routes such as intranasal, sublingual, transdermal, intravenous and rectal have been studied. Experimental studies using APO help to shed light on pathophysiological aspects of PD as well as on various side effects of dopamine agonist treatment including sedation and sleep induction.