Mexiletine for the Management of Ventricular Arrhythmias in Ischemic Heart Disease

Mexiletine, a type IB anti arrhythmic agent, has recently been released in the United States for use in the oral treatment of ventricular arrhythmias. It is as effective as other group IB and LA drugs, and less effective than group 1C agents such as propafawne, flecainide, and amiodarone; however, it has the advantage of being associated with fewer serious adverse effects. Mexiletine will control ventricular tachycardia in patients with drug-resistant arrhythmias in 20–30% of cases; in unselected populations it may abolish VT in 50–96%. It is recommended that mexiletine be combined with beta blockers and/or group IA drugs for treating resistant arrhythmias. Efficacy may be increased and adverse side effects reduced through use of smaller dosages and combination therapy.