Mexiletine Capsule

Mexiletine is a class 1B, sodium channel blocker, anti-arrhythmia drug which is used to treat chronic ventricular arrhythmias in dogs. The mechanism of action is similar to lidocaine. Mexiletine is used to treat ventricular arrhythmias including PVC's and ventricular tachycardia. If an animal has responded well to lidocaine during an acute episode, it is likely to respond well to mexiletine. Mexiletine may be used to treat inherited cardiomyopathy in Boxers and dilated cardiomyopathy in Doberman pinschers.

Key Benefits

• Sodium channel blocker similar to lidocaine
• Used to treat ventricular arrhythmias (PVC's and ventricular tachycardia) in dogs
• If monotherapy is not sufficient either atenolol or sotalol may be used in conjunction

How It Works

Mexiletine is well absorbed orally and has a bioavailability of approximately 85%. It is primarily excreted in the urine although approximately 10% is metabolized by the liver and excreted in the feces. The half-life of this drug may be prolonged in animals with reduced cardiac output, or after an acute myocardial infarction. The half-life may also be prolonged in animals with hepatic dysfunction or severe kidney disease.

Indications

Mexiletine Hydrochloride Capsules USP are indicated for the treatment of documented ventricular arrhythmias, such as sustained ventricular tachycardia, that, in the judgment of the physician, are life- threatening. Because of the proarrhythmic effects of mexiletine, its use with lesser arrhythmias is generally not recommended. Treatment of patients with asymptomatic ventricular premature contractions should be avoided.

Initiation of mexiletine treatment, as with other antiarrhythmic agents used to treat life-threatening arrhythmias, should be carried out in the hospital.

Antiarrhythmic drugs have not been shown to enhance survival in patients with ventricular arrhythmias.