Prescription medication · Class IB Antiarrhythmic

mexiletine

Also sold as Mexitil. Mexiletine is used to treat serious, life-threatening ventricular arrhythmias, like sustained ventricular tachycardia.

Data updated 2026-05-15

408
FDA reportsRarely reported
14
InteractionsSeveral interactions
$0.27
Generic price (NADAC)

What the data shows

mexiletine (Mexitil) is a prescription Class IB Antiarrhythmic, among the least-reported drugs the FDA tracks (408 FDA reports), with 14 documented drug interactions.

Reporting volume reflects how widely a drug is used and studied, not how dangerous it is, a FAERS report documents a temporal association, never proof of cause.

mexiletine (Mexitil) is a prescription Class IB Antiarrhythmic. Mexiletine is used to treat serious, life-threatening ventricular arrhythmias, like sustained ventricular tachycardia.

Mexiletine is a medicine used to treat life-threatening heart rhythm problems. It helps to stabilize your heartbeat.

Drug Pricing (NADAC)

Generic Price

$0.27/unit

Generic Available

Yes (8 manufacturers)

Pricing data from NADAC (CMS), effective December 18, 2024. Compare all drug costs →

Compare with Another Drug → Full Side Effects Report →

What it does

Mexiletine is used to treat serious, life-threatening ventricular arrhythmias, like sustained ventricular tachycardia.

Common side effects

Nausea, Vomiting, Heartburn

Key warnings

Mexiletine may increase the risk of death or cardiac arrest in some patients with a history of heart attack.

The sections below are summarized in plain English from mexiletine's FDA-approved prescribing information. They describe what the official label says, and are not personal medical advice.

How It Works

Mexiletine belongs to a class of drugs called antiarrhythmics. It works by slowing down the electrical signals in your heart. This helps to make your heartbeat more regular.

Side Effects (from patient reports)

Based on 408 FDA adverse event reports.

Most-reported reactions

Adverse reactions in FAERS for mexiletine, by number of reports

reports

What this shows Bars show how often each reaction was reported, not how likely it is to happen, a report records a temporal association, never proof that the drug caused it.

Source FDA Adverse Event Reporting System (FAERS) As of 2025

Reports over time

Adverse-event reports filed for mexiletine each year to the FDA Adverse Event Reporting System (FAERS).

010203040 20042007201020132016201920222025 9

Year-to-year volume tracks usage, prescribing, and scrutiny, not a change in per-patient risk. Source: FDA FAERS.

Where mexiletine sits

mexiletine has more FDA adverse-event reports than 3% of the drugs FAERS tracks. A high position reflects how widely a drug is used and watched, not how dangerous it is.

fewest reports most reports

Percentile across all drugs PlainMeds tracks by FAERS report volume. The dot is mexiletine; the line is the median (50th percentile).

FDA Adverse Event Report Analysis

Detailed analysis of 408 reports from the FDA Adverse Event Reporting System (FAERS). Reports span 2004–2025.

Total Reports

408

Reports Mentioning Death

75

18.4% of reports — not proof of cause

Hospitalization Reports

253

Top Indication

Product Used For Unknown Indication

Gender Distribution

Female 158 (41%)
Male 230 (59%)

Age Distribution

0–17 15
18–44 24
45–64 97
65–74 82
75+ 107

Most Reported Adverse Reactions (FAERS)

# Reaction Reports
2 FATIGUE 31
3 VENTRICULAR TACHYCARDIA 31
4 DYSPNOEA 26
5 NAUSEA 24
6 POOR QUALITY SLEEP 24
7 IMPAIRED WORK ABILITY 23
8 IMPAIRED QUALITY OF LIFE 22
9 PYREXIA 22
10 CARDIAC FAILURE 18
11 HYPERTENSION 18
12 PNEUMONIA 18
13 CONTUSION 15
14 ALANINE AMINOTRANSFERASE INCREASED 14
15 CARDIAC FAILURE CONGESTIVE 14
16 DIARRHOEA 14

Reactions in Death Reports

PNEUMONIA 11
DEATH 10
CARDIAC ARREST 8
CARDIAC FAILURE 8
NAUSEA 8
CARDIAC FAILURE CONGESTIVE 7
PAIN 7
DYSPNOEA 6
RENAL FAILURE 6
THROMBOCYTOPENIA 6

Reactions in Hospitalization Reports

FATIGUE 31
POOR QUALITY SLEEP 24
IMPAIRED WORK ABILITY 23
IMPAIRED QUALITY OF LIFE 22
DYSPNOEA 20
VENTRICULAR TACHYCARDIA 20
PYREXIA 18
HYPERTENSION 17
PNEUMONIA 15
CONTUSION 13

Source: FDA FAERS (Adverse Event Reporting System) Reports are voluntary and do not establish causation

Serious Warnings

Mexiletine may increase the risk of death or cardiac arrest in some patients with a history of heart attack. It should only be used for life-threatening ventricular arrhythmias. This medicine can also cause liver problems, especially if you have congestive heart failure or ischemia.

Known Drug Interactions

Drug Interactions Antiarrhythmic Drugs LIDODERM should be used with caution in patients receiving Class I antiarrhythmic drugs (such as tocainide and mexiletine) since the toxic effects are additive and potentially synergistic.

Mechanism: These drugs have similar effects on the body, so taking them together can cause their toxic side effects to build up. This makes the risk of a bad reaction much higher than taking just one.

A variety of antiarrhythmics such as quinidine or propranolol were also added, sometimes with improved control of ventricular ectopy. ECG intervals (PR, QRS, and QT) were not affected by concurrent mexiletine and digoxin, diuretics, or propranolol.

Mechanism: These two heart medicines can be used together to help control irregular heartbeats without changing the heart's electrical timing.

minor digoxin

ECG intervals (PR, QRS, and QT) were not affected by concurrent mexiletine and digoxin, diuretics, or propranolol. Mexiletine does not alter serum digoxin levels but magnesium-aluminum hydroxide, when used to treat gastrointestinal symptoms due to mexiletine, has been reported to lower serum digoxin levels.

Mechanism: Mexiletine does not change the amount of digoxin in your blood or affect the heart's electrical signals when taken together.

In another formal study (n = 8 extensive and n = 7 poor metabolizers of CYP2D6), coadministration of propafenone did not alter the kinetics of mexiletine in the poor CYP2D6 metabolizer group. In this crossover steady state study, the pharmacokinetics of propafenone were unaffected in either phenotype by the coadministration of mexiletine. Addition of mexiletine to propafenone did not lead to further electrocardiographic parameters changes of QRS, QT c , RR, and PR intervals than propafenone alone.

Mechanism: These two drugs do not appear to interfere with how the body processes either medication. They also do not cause extra changes to the heart's electrical activity when used together.

Concurrent use of mexiletine and theophylline may lead to increased plasma theophylline levels. One controlled study in eight normal subjects showed a 72% mean increase (range 35 to 136%) in plasma theophylline levels. Theophylline plasma levels returned to pre-mexiletine values within 48 hours after discontinuing mexiletine.

Mechanism: Mexiletine can slow down the removal of theophylline from your body, which makes the amount of theophylline in your blood go up.

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This is a plain-language summary of FDA-label interaction records and does not provide individual medication-combination directions.

Common Questions

Can I take mexiletine if I have a pacemaker?
Mexiletine is contraindicated in the presence of second- or third-degree AV block if no pacemaker is present.
What should I do if I experience side effects?
Talk to your doctor if you experience side effects. They may adjust your dose or recommend ways to manage the side effects.
Can I drink alcohol while taking mexiletine?
Ask your doctor if it is safe to drink alcohol while taking mexiletine.
Will mexiletine cure my arrhythmia?
Mexiletine helps control your arrhythmia, but it may not cure it.
How long will I need to take mexiletine?
Your doctor will determine how long you need to take mexiletine.
Can I stop taking mexiletine on my own?
Do not stop taking mexiletine without talking to your doctor first.
Does mexiletine interact with other medications?
Yes, mexiletine can interact with other medications. Tell your doctor about all the medicines you take.
Can I drive while taking mexiletine?
Mexiletine can cause dizziness or lightheadedness. Be careful driving or operating machinery until you know how it affects you.
What is the best time of day to take mexiletine?
Take mexiletine as directed by your doctor, usually with food or antacids.
How will I know if mexiletine is working?
Your doctor will monitor your heart rhythm to see if mexiletine is working.
What are the common side effects of mexiletine?
The registry lists Nausea, Vomiting, Heartburn, Dizziness, Lightheadedness among the most-reported FAERS reaction terms for mexiletine. The compiled record contains 408 FDA adverse-event reports. These counts are not an individual symptom assessment.
Does mexiletine interact with other medications?
The registry has 14 documented interaction rows for mexiletine. Notable source-record pairings include lidocaine topical, propranolol, digoxin. These rows are not a complete medication review.
What drug class is mexiletine?
mexiletine belongs to the Class IB Antiarrhythmic drug class. It requires a prescription (Rx). Mexiletine is used to treat serious, life-threatening ventricular arrhythmias, like sustained ventricular tachycardia.
What pregnancy or breastfeeding source fields are listed for mexiletine?
The FDA label for mexiletine contains product-specific pregnancy or breastfeeding language. PlainMeds does not apply that source text to an individual.

Other drugs grouped near mexiletine - same-class peers and common alternatives.

Compare mexiletine vs adenosine side-by-side →

Compare beyond drug class

Nationwide peers by FAERS volume & death-report share

Two PlainMeds-derived comparison paths for mexiletine: nearest FDA FAERS report volume and nearest death-report share among drugs with at least 1,000 logged reports, excluding same-class neighbors listed above. Counts reflect reporting volume, not proven individual harm.

Medication Guides

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What the FDA Data Shows for mexiletine

The FDA label for mexiletine (sold under brand names such as Mexitil) classifies it as a prescription-only medication in the Class IB Antiarrhythmic class. Mexiletine is used to treat serious, life-threatening ventricular arrhythmias, like sustained ventricular tachycardia. Official labeling lists 7 commonly reported side effects, including Nausea, Vomiting, Heartburn.

Post-market surveillance from the FDA Adverse Event Reporting System (FAERS) captures real-world experience. For this drug, FAERS contains 408 voluntary reports. The database also lists 14 documented drug interactions derived from FDA labeling, with the top-flagged interaction rated moderate severity. NADAC pricing from CMS shows a generic unit cost of $0.27.

Report counts do not establish causation, a FAERS entry documents a temporal association, not proof that the drug produced the outcome. Widely prescribed medications naturally accumulate more reports than niche therapies, so raw totals must be interpreted alongside total exposure. Shortage status, recall history, and patent information are separate source-record fields. This page is a public FDA/CMS registry and does not provide medical, treatment, substitution, or medication-change directions.

Data Sources

Drug labeling: FDA Drug Labels (SPL/DailyMed). Adverse events: FDA Adverse Event Reporting System (FAERS). Pricing: CMS National Average Drug Acquisition Cost (NADAC).

FAERS reports are voluntary and do not establish causation. Drug interactions are derived from FDA labeling and clinical references. This registry does not provide medication decisions.

Last updated: January 15, 2024

PlainMeds is rendered directly from FDA openFDA/FAERS extracts, DailyMed labels, and CMS drug-pricing files, no number is typed in by an editor. FAERS counts, recalls, shortages, and price figures on this page are queried live from those federal extracts. See our editorial standards & corrections policy, the methodology behind these numbers, or report a data error. Data current as of 2026-05-15. Primary sources: openFDA / FAERS, DailyMed and CMS Part B ASP.

Data currency: FDA FAERS adverse-event reports through 2025, CMS NADAC acquisition-cost pricing effective December 2024, compiled from the source snapshot dated . See our methodology for per-source dates and refresh cadence. Spot a figure that looks wrong? Report a data issue.

All federal data sources used on this page