Drug interactions between Apokyn and Zithromax

azithromycin ↔ apomorphine

Applies to:Zithromax (azithromycin) and Apokyn (apomorphine)

MONITOR: Apomorphine may cause modest prolongation of the QTc interval. Theoretically, coadministration with other agents that can prolong the QT interval may result in additive effects and increased risk of ventricular arrhythmias including torsade de pointes and sudden death. In addition, some of these agents (e.g., phenothiazines, tricyclic antidepressants) may cause additive sedative and hypotensive effects with apomorphine. Apomorphine doses greater than 6 mg have been associated with minimal increases of the QT interval. The average QTc prolongation was 1 msec at 6 mg and 7 msec at 8 mg. Two patients experienced large increases of more than 60 msec with 2 mg and 6 mg doses. Torsade de pointes has not been reported with apomorphine alone at recommended doses. In general, the risk of an individual agent or a combination of agents causing ventricular arrhythmia in association with QT prolongation is largely unpredictable but may be increased by certain underlying risk factors such as congenital long QT syndrome, cardiac disease, and electrolyte disturbances (e.g., hypokalemia, hypomagnesemia). In addition, the extent of drug-induced QT prolongation is dependent on the particular drug(s) involved and dosage(s) of the drug(s).

MANAGEMENT: Caution is recommended when apomorphine is administered concomitantly with drugs that prolong the QT interval, especially to patients with underlying risk factors. Patients should be advised to seek medical attention if they experience symptoms that could indicate the occurrence of torsade de pointes such as dizziness, palpitations, or syncope. If taking drugs that also cause CNS or orthostatic effects, patients should be made aware of the possibility of additive effects (e.g., drowsiness, dizziness, lightheadedness) and counseled to avoid activities requiring mental alertness until they know how these agents affect them.