MedicinePOM

Mexiletine

An antiarrhythmic medicine for life-threatening abnormal heart rhythms.

Clinical information

Common uses

life-threatening ventricular arrhythmias such as sustained ventricular tachycardia

Common side effects

heartburn, nausea or vomiting
dizziness or lightheadedness
tremor
coordination difficulties
nervousness

Cautions

reserved for life-threatening rhythm problems (boxed warning)
treatment is started in hospital
not with cardiogenic shock or certain heart block
stop if signs of severe drug reaction (DRESS) appear

Interactions

fluvoxamine or propafenone (raise mexiletine levels)
phenytoin, rifampin or phenobarbital (lower mexiletine levels)
theophylline (its levels rise sharply)
cimetidine (levels may change)
caffeine (cleared more slowly)

Reference information, not medical advice — always follow your doctor or pharmacist. Source: DailyMed, dailymed.nlm.nih.gov, mexiletine hydrochloride label, setid 1c6024e9-760b-40a4-9ef1-b75b269c582a (accessed 2026-08-16)

Approved brands & formulations4

Brand name	Dosage form	Strength	Importer	Category
Mexitil	Capsule	50 mg	—	POM
Mexitil	Capsule	50 mg	authorized medicine importers	POM
Mexitil	Capsule	150 mg	—	POM
Mexitil	Capsule	150 mg	authorized medicine importers	POM