Mexiletine: Side Effects, Uses & Monitoring

Facts extracted from current FDA product labeling for Mexiletine. Educational only — not medical advice.

Reported adverse reactions

ReactionHighest frequency reported*
Nausea/vomiting/heartburn39.6%
Nausea/vomiting/ heartburn39.3%
Diarrhea33.2%
Dizziness/lightheadedness26.4%
Changes in sleep habits16.3%
Dry mouth14.5%
Tremor13.2%
Constipation11.6%
Nervousness11.3%
Palpitations10.2%
Dyspnea/respiratory10.2%
Coordination difficulties9.4%
Chest pain7.5%
Headache7.5%
Blurred vision/visual disturbances7.5%
Arthralgia5.1%
Weakness4.1%
Tinnitus4.1%
Paresthesias/numbness3.8%
Rash3.8%

*Highest percentage across placebo-controlled trial tables summarized in current labeling.

Labeled uses

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.

Source: FDA labeling via NIH DailyMed (set c528aae3…). Not affiliated with FDA or NIH.

Medical disclaimer: Always consult a qualified healthcare professional about any medication.