Advice for healthcare professionals:
- Before starting treatment, carefully consider whether the benefits of concomitant apomorphine and domperidone treatment outweigh the small increased risk of cardiac side effects
- Discuss the benefits and risks of apomorphine with patients and carers and advise them to contact their doctor immediately if they develop palpitations or syncopal symptoms during treatment
- Check the QT-interval before starting domperidone, during the apomorphine initiation phase and if clinically indicated thereafter (eg if a QT-prolonging or interacting drug is started or if symptoms of cardiac side effects are reported)
- Regularly review domperidone treatment to ensure patients take the lowest effective dose for the shortest duration
- Advise patients to inform their doctor of any changes that could increase their risk of arrhythmia, such as:
- symptoms of cardiac or hepatic disorders
- conditions that could cause electrolyte disturbances (eg, gastroenteritis or starting a diuretic)
- starting any other medicines
- Please continue to report suspected side effects to apomorphine, domperidone, or any other medicine on a Yellow Card
Apomorphine (brand names: APO-go, Dacepton) is a dopamine agonist used to treat refractory motor fluctuations in people with Parkinson’s disease. Domperidone (brand names: Motilium, Dismotil) is usually started at least two days before apomorphine to control the expected side effects of nausea and vomiting.
Domperidone and the risk of cardiac side effects
In 2014, a review by EU medicines regulators concluded that domperidone is associated with a small increased risk of QT-interval prolongation, serious ventricular arrhythmias, and sudden cardiac death. A higher risk was observed in people older than 60 years, people taking daily oral doses of more than 30 mg, and in those taking other QT-prolonging medicines or cytochrome P450 3A4 inhibitors at the same time as domperidone. As a result of this review, the licensed indication for domperidone was restricted to relief of nausea and vomiting, the licensed dose was reduced, and several contraindications were introduced (see Drug Safety Update article from May 2014 for further details).
Apomorphine with domperidone and the risk of QT-prolongation
Apomorphine can increase the risk of QT-prolongation at high doses.
A review by EU medicines regulators of the safety of concomitant apomorphine and domperidone use has recently finished. This review concluded that health professionals should take the precautions listed above to reduce the risk of QT-prolongation. The risk of QT-prolongation may be increased in people on concomitant apomorphine and domperidone who have certain risk factors, including:
- pre-existing QT-interval prolongation
- serious underlying cardiac disorders such as heart failure
- severe hepatic dysfunction
- significant electrolyte disturbances
- concomitant drug therapy that may increase domperidone levels (eg, cytochrome P450 3A4 inhibitors)
Drug Safety Update article on domperidone from May 2014
Article citation: Drug Safety Update Vol 9 issue 9 April 2016: 5.