Sustained ventricular tachycardia occurring during propafenone therapy

: The arrhythmogenic action of antiarrhythmic agents, especially the class I antiarrhythmic drugs, is well known. However till now only few such side effects were reported for propafenone in comparison with other class I antiarrhythmic drugs. We report a case of asymptomatic monomorphic ventricular tachycardia occurring during propafenone therapy with normal plasma level. Stopping this drug was quickly followed by recovery of sinus rhythm.