Apomorphine is a subcutaneously administered dopamine receptor agonist used predominantly in the therapy of hypomobility of advanced Parkinson disease. The use of apomorphine has been limited, but it has not been associated with serum enzyme elevations during treatment nor has it been implicated in cases of acute liver injury.


Apomorphine (a" poe mor' feen) is a subcutaneously administered dopamine receptor agonist which has moderate affinity for the D2, D3, and D5 class of dopamine receptors in the central nervous system and little activity against the D1 class. It also has some alpha adrenergic activity. Apomorphine was shown to improve motor function in animal models of Parkinson disease and in clinical trials, was shown to decrease hypomobility in patients with advanced Parkinsonism. Apomorphine was approved for use in the United States in 2004, but had been used in Europe for more than a decade. Current indications are for acute and intermittent treatment of hypomobility of advanced Parkinson disease. It is also used for acute dystonic reactions. Apomorphine is available in a liquid solution of 10 mg/mL under the brand name Apokyn. It is given in 0.2 to 0.6 mL doses subcutaneously as needed up to 3 times daily. Apomorphine injections usually cause nausea and vomiting requiring antiemetics. It can cause hypotension, gastrointestinal upset, anxiety, confusion, dizziness, headache, hallucinations, vivid dreams and insomnia, symptoms typical of dopaminergic stimulation.


Apomorphine has not been reported to cause serum aminotransferase elevations or clinically apparent acute liver injury, but its use has been limited and is typically given in low doses for a limited period of time. Thus, if apomorphine causes liver injury it must be rare.

Likelihood score: E (unlikely cause of clinically apparent liver injury).

Mechanism of Injury

The metabolism of apomorphine has not been well defined; it appears to be minimally metabolized in the liver.

Drug Class: Antiparkinson Agents

Other Drugs in the Subclass, Dopamine Receptor Agonists: Bromocriptine, Pergolide, Pramipexole, Ropinirole, Rotigotine



Apomorphine – Apokyn®


Antiparkinson Agents


Product labeling at DailyMed, National Library of Medicine, NIH



References updated: 20 July 2017

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