Comparative Study of the Effects of Erythromycin and Roxithromycin on Action Potential Duration and Potassium Currents in Canine Purkinje Fibers and Rabbit Myocardium

Abstract
Background: Erythromycin and roxithromycin are macrolide antibiotics in common clini cal use. Erythromycin occasionally produces life-threatening arrhythmias (torsades de pointes) by blocking the outward potassium current responsible for repolarization of the cardiac action potential.