Heart arrhythmias in pets can be treated with Mexiletine Hydrochloride Capsule. Mexiletine hydrochloride is specifically formulated for use in dogs who have been diagnosed with a chronic ventricular arrhythmia. However, it may also be effective for treating dilated cardiomyopathy in Doberman Pinschers and inherited cardiomyopathy in Boxers. Mexiletine hydrochloride is a class 1B sodium channel blocker that has a mechanism of action similar to that of lidocaine. Sold by the capsule.How it Works

Mexiletine offers about an 85% bioavailability and is orally well-absorbed. It is partially metabolized by the liver (10%) and excreted through the feces, and the rest is excreted through the urine. Animals who have reduced cardiac output, severe disease of the kidneys, hepatic dysfunction, or have experienced acute myocardial infarction could experience a prolonged half-life.

Special Precautions

Mexiletine should be cautiously administered to animals with:

• Seizure disorders
• Hypotension
• Liver dysfunction
• Myocardial infarction
• Congestive heart failure
• Cardiogenic shock
• Abnormal sinus node function
• Abnormal intraventricular conduction
• 2nd or 3rd degree AV heart block

Overdose Information

Overdose with mexiletine carries a significant risk of toxicity. It is reported in the human literature that central nervous system signs precede cardiovascular signs. In experimental work in dogs, a four fold overdose consistently produced CNS signs within 10 minutes of oral administration. If recognized in time, GI emptying protocol should be attempted in conjunction with urinary acidification and supportive care.

Side Effects

The most frequently reported adverse reactions are GI tract-related and could include vomiting or nausea. These symptoms usually improve when Mexiletine is given with food.

Other potential reactions are central nervous system-related and could include:

• Cardiac symptoms (chest pain or PVCs)
• Shortness of breath
• Trembling
• Loss of balance
• Dizziness

Storage

Store in a dry and cool place.

Tips

Follow your veterinarian's recommendations for administration.