Apomorphine

How it works

It directly stimulates D1 and D2 dopamine receptors in the brain, rapidly restoring dopaminergic activity and reducing 'off'-period motor symptoms.

Prescribing in practice

• It is strongly emetogenic, so an antiemetic such as domperidone is usually started beforehand, while metoclopramide and other dopamine-antagonist antiemetics must be avoided.
• Initiation requires specialist supervision with assessment of standing and lying blood pressure because of the risk of pronounced hypotension.
• It can cause impulse-control disorders, daytime somnolence and injection-site nodules, and the cardiovascular risk profile including QT effects should be considered.

Monitoring

Monitor blood pressure (including for postural drops) on initiation, inspect injection sites, and review for impulse-control disorders and excessive daytime sleepiness.

Counselling the patient

• Take the antiemetic as advised before starting, but avoid metoclopramide for nausea.
• Tell the team about any new gambling, shopping, or other compulsive urges.
• Rotate injection sites and report painful lumps or sudden drowsiness.

Evidence & guidelines

Use is supported by NICE guidance on Parkinson's disease for managing motor fluctuations with subcutaneous apomorphine.