Drug Interaction Report

CONTRAINDICATED: Severe hypotension and loss of consciousness has been reported during the concomitant use of apomorphine and ondansetron. The mechanism is unknown. Other 5-HT3 antagonists may also interact. In addition, dolasetron, palonosetron, and apomorphine have been associated with varying degrees of QT interval prolongation, which may increase the risk of torsades de pointes in susceptible patients.

MANAGEMENT: The concomitant use of apomorphine and 5-HT3 antagonists is contraindicated by the manufacturer.

GENERALLY AVOID: Alcohol and apomorphine may have additive hypotensive and sedative effects. Coadministration of 0.6 or 0.3 g/kg of ethanol with apomorphine in healthy subjects resulted in greater decreases in blood pressure compared to apomorphine alone. The mean largest decrease (the mean of each subject's largest drop in blood pressure measured within 6 hours after apomorphine administration) in standing systolic and diastolic blood pressure was 6.7 and 8.4 mmHg, respectively, with apomorphine alone. When coadministered with 0.6 g/kg of ethanol (equivalent to approximately 3 standardized alcohol-containing beverages), the mean largest decrease in standing systolic and diastolic blood pressure was 11.3 and 12.6 mmHg, respectively (standing systolic and diastolic blood pressure decreased by as much as 61 and 51 mmHg, respectively, in this group). When coadministered with 0.3 g/kg of ethanol, the mean largest decrease in standing systolic and diastolic blood pressure was 8.4 and 7.1 mmHg, respectively.

MANAGEMENT: Patients should be advised to avoid consumption of alcohol during apomorphine treatment.