When administered alone increases risk of sudden death by 2 times and when combines with verapamil or diltiazem increased the risk by 5 fold.
Prolongs cardiac repolarization and can be associated with torsades de pointes.
Metabolized by cytochrome-P450 3A isozymes and calcium channel blockers can inhibit such metabolism increasing the plasma levels of erythromycin increasing the risk for sudden death and ventricular arrhythmias.