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Mexitil (MEXILETINE)
Mexitil works by blocking abnormal electrical signals in the heart to restore a normal heartbeat.
Mexitil (Mexiletine) is a small molecule antiarrhythmic medication developed by Lupin Europe GmbH and currently owned by Boehringer Ingelheim. It targets the 5-hydroxytryptamine receptor 2B and is used to treat myotonic disorder and ventricular arrhythmia. Mexitil was FDA approved in 1985 and is now off-patent, with multiple generic manufacturers available. The medication has a half-life of 9.9 hours and bioavailability of 87%. It is a useful treatment option for patients with certain arrhythmias.
At a glance
| Generic name | MEXILETINE |
|---|---|
| Sponsor | Boehringer Ingelheim |
| Drug class | Antiarrhythmic |
| Target | 5-hydroxytryptamine receptor 2B |
| Modality | Small molecule |
| Therapeutic area | Metabolic |
| Phase | FDA-approved |
| First approval | 1985 |
Mechanism of action
Mechanism of Action. Mexiletine hydrochloride is local anesthetic, antiarrhythmic agent, structurally similar to lidocaine, but orally active. In animal studies, mexiletine has been shown to be effective in the suppression of induced ventricular arrhythmias, including those induced by glycoside toxicity and coronary artery ligation. Mexiletine, like lidocaine, inhibits the inward sodium current, thus reducing the rate of rise of the action potential, Phase 0. Mexiletine decreased the effective refractory period (ERP) in Purkinje fibers. The decrease in ERP was of lesser magnitude than the decrease in action potential duration (APD), with resulting increase in the ERP/APD ratio.
Approved indications
- Ventricular Arrhythmias
Boxed warnings
- BOXED WARNING WARNINGS Mortality In the National Heart, Lung and Blood Institute’s Cardiac Arrhythmia Suppression Trial (CAST), a long-term, multicentered, randomized, double-blind study in patients with asymptomatic non-life-threatening ventricular arrhythmias who had a myocardial infarction more than six days but less than two years previously, an excessive mortality or non-fatal cardiac arrest rate (7.7%) was seen in patients treated with encainide or flecainide compared with that seen in patients assigned to carefully matched placebo-treated groups (3.0%). The average duration of treatment with encainide or flecainide in this study was ten months. The applicability of the CAST results to other populations (e.g., those without recent myocardial infarction) is uncertain. Considering the known proarrhythmic properties of mexiletine and the lack of evidence of improved survival for any antiarrhythmic drug in patients without life-threatening arrhythmias, the use of mexiletine as well as other antiarrhythmic agents should be reserved for patients with life-threatening ventricular arrhythmia. Acute Liver Injury In postmarketing experience abnormal liver function tests have been reported, some in the first few weeks of therapy with mexiletine hydrochloride. Most of these have been observed in the setting of congestive heart failure or ischemia and their relationship to mexiletine hydrochloride has not been established.
Common side effects
- Nausea/Vomiting/Heartburn
- Dizziness/Lightheadedness
- Tremor
- Nervousness
- Coordination Difficulties
- Changes in Sleep Habits
- Palpitations
- Chest Pain
- Headache
- Blurred Vision/Visual Disturbances
- Dyspnea/Respiratory
- Rash
Drug interactions
- fluvoxamine
- propafenone
- phenytoin, rifampin, phenobarbital
- cimetidine
- theophylline
Key clinical trials
- Non-Invasive Programmed Stimulation (NIPS) to Guide the Subsequent VT Therapeutic Strategies (NA)
- The Efficacy and Safety of Once Daily Mexiletine PR in Patients With Myotonic Dystrophy Type 1 and Type 2 (PHASE3)
- An Open-Label Extension Study to Evaluate the Long-Term Safety and Efficacy of Once Daily Mexiletine PR in Patients With Myotonic Dystrophy Type 1 and Type 2 Who Have Completed MEX-DM-302 Study. (PHASE3)
- An Open-Label, Randomized, Cross-Over Study to Investigate the Efficacy and Safety of Mexiletine PR Compared to Mexiletine IR (PHASE3)
- Prospective, Long Term, Observational Study (Patient Registry) of Paediatric Myotonic Disorders
- Open-label Extension Study in Paediatric Patients Who Have Completed the MEX-NM-301 Study. (NA)
- An Observational Study in Adult Patients With Non-dystrophic Myotonic Disorders
- Clinical Trial of Mexiletine Hydrochloride for Spinal and Bulbar Muscular Atrophy (PHASE2,PHASE3)
Primary sources
Every claim on this page is sourced from regulatory or scientific primary sources. See our editorial policy for full methodology.
| Source | Used for |
|---|---|
| FDA label | Mechanism, indications, dosing, boxed warnings, drug interactions |
| ClinicalTrials.gov | Trial enrolment, design, endpoints, results |
Competitive intelligence
For the full competitive landscape — auto-detected comparators, recent regulatory actions across the set, upcoming PDUFA, patent timeline, sponsor landscape:
- Mexitil CI brief — competitive landscape report
- Mexitil updates RSS · CI watch RSS
- Boehringer Ingelheim portfolio CI