Mexitil is the brand name for mexiletine hydrochloride. It’s an oral antiarrhythmic medication (class IB) used to treat certain heart rhythm problems and, in some contexts, other conditions.
What it does
- Mechanism: Blocks sodium channels in heart muscle, helping to stabilize electrical activity and reduce abnormal heart rhythms.
- Primary uses:
- Ventricular arrhythmias (e.g., ventricular ectopy, certain sustained ventricular tachycardias)
- Sometimes used in specific inherited conditions like long QT syndrome type 3
- Off-label/special situations include some neuromuscular disorders (e.g., myotonia congenita)
What to know about dosing and administration
- Dosing is individualized and must be guided by a clinician. It’s usually given in divided doses throughout the day.
- Take it exactly as prescribed. If you have trouble tolerating the dose or forgot a dose, check with your clinician before adjusting.
- It’s often advised to take mexiletine with or shortly after meals to reduce stomach upset.
- Regular monitoring (see below) is usually needed when you start or adjust therapy.
Key safety information
- Do not use if you have:
- Significant conduction problems in the heart (e.g., AV block) unless you have a pacemaker
- Severe heart failure or a history of certain serious heart rhythms unless advised by a doctor
- Known allergy to mexiletine or similar medicines
- Common side effects: dizziness, tremor, headache, nausea, vomiting, constipation, blurred vision, or fatigue.
- More serious (less common) risks: bradycardia (slow heart rate), heart block, fainting, severe drops in blood pressure, or allergic reactions. Seizures or confusion can occur at high levels.
- Rare liver or blood abnormalities can occur with some patients; report unusual tiredness, yellowing of skin/eyes, dark urine, or bleeding easily.
Drug interactions and cautions
- Mexiletine can interact with other antiarrhythmics and drugs that affect heart rhythm or sodium handling, increasing the risk of dangerous rhythms.
- It may interact with certain antibiotics, antifungals, antidepressants, and other medicines that affect liver enzymes (CYPs). Some foods or supplements can also alter levels.
- Tell your clinician about all medicines you take (prescription, over-the-counter, vitamins, and herbal products) and any existing medical conditions.
Pregnancy and breastfeeding
- If you are pregnant or planning pregnancy, talk to your clinician. Mexiletine can affect a fetus; use only if clearly needed and under close monitoring.
- Breastfeeding while taking mexiletine should be discussed with a clinician, as the drug can pass into breast milk.
What would you like to know specifically?
- Are you looking for typical dosing ranges, side effects, interactions, or something else? If you’re currently prescribed Mexitil, sharing your exact context (condition being treated, other meds, and any symptoms) can help me tailor the information.