OpenClaim

Mexiletine Side Effects

The most commonly reported side effects of mexiletine include off label use, fatigue, and weight increased, based on 2,943 FDA adverse event reports from 2004 to 2025. 12.1% of reports found the drug to be ineffective.

Mexiletine side effects

Percentages show how often each reaction appears relative to total reports for mexiletine.

1
Drug Ineffective12.1%356
2
Off Label Use6.0%177
3
Fatigue4.9%143
4
Weight Increased4.1%120
5
Blood Glucose Increased3.3%98
6
Ventricular Tachycardia3.1%91
7
Insomnia3.0%87
8
Nausea2.8%83
9
Contusion2.5%75
10
Poor Quality Sleep2.5%73
11
Drug Ineffective2.4%72
12
Dizziness2.4%71
13
Hypertension2.3%68
14
Diarrhoea2.3%67
15
Herpes Zoster2.3%67

These are voluntary reports and do not establish that mexiletine caused these reactions.

Report severity

88.0%Serious2,589 reports
50.3%Hospitalizations1,480 reports
16.6%Fatal488 reports

Seriousness is determined by the reporter, not by OpenClaim.

Mexiletine drug interactions

Other drugs that appear in adverse event reports alongside mexiletine. Drugs flagged as a suspected cause appear in the first column. Drugs taken at the same time but not suspected appear in the second.

Also suspected

1
Amiodarone-hydrochloride11.8%348
2
Lidocaine9.4%276
3
Insulin5.5%162
4
Pregabalin5.0%148
5
Metoprolol4.4%129
6
Amitriptyline-hydrochloride4.0%117
7
Valsartan3.8%113
8
Ketamine-hydrochloride3.8%112
9
Memantine-hydrochloride3.7%109
10
Amlodipine3.6%107
11
Clonidine3.5%102
12
Gabapentin3.4%101
13
Aspirin3.3%98
14
Prednisone3.3%98
15
Capsaicin3.3%98

Taken alongside

1
Furosemide17.1%502
2
Aspirin15.5%456
3
Spironolactone11.2%329
4
Carvedilol9.2%270
5
Amiodarone-hydrochloride8.9%262
6
Warfarin8.8%260
7
Atorvastatin-calcium8.8%259
8
Metoprolol8.6%253
9
Insulin6.8%201
10
Acetaminophen6.8%199
11
Amlodipine5.8%172
12
Levothyroxine-sodium5.6%165
13
Gabapentin5.5%163
14
Digoxin5.5%161
15
Prednisone5.3%155

Co-occurrence in adverse event reports does not establish a drug interaction. Patients often take multiple medications, and these lists reflect prescribing patterns rather than causal relationships. Consult a healthcare provider about potential drug interactions.

Who reports mexiletine side effects

37.8% of mexiletine adverse event reports involve female patients and 56.4% involve male patients. The largest age group is elderly at 48%. These figures reflect who reports side effects, not underlying risk.

Sex

Female37.8%
Male56.4%
Unknown5.8%

Age group

< 23.2%
2–111.6%
12–172.1%
18–6445.4%
65+47.8%

What is mexiletine used for

Conditions and purposes for which patients were taking mexiletine when the adverse event was reported.

Abdominal DistensionAcute Myocardial InfarctionAdverse EventAllodyniaAnalgesic EffectAnalgesic TherapyAngina PectorisAngiopathyAnxietyAortic Valve StenosisArrhythmiaArrhythmia ProphylaxisArrhythmogenic Right Ventricular DysplasiaAtrial FibrillationAtrioventricular Block

Showing 15 of 218 indications

Mexiletine brand names and reporting trend

Mexiletine is sold under the brand name Mexiletine Hydrochloride.

Brand names

Mexiletine Hydrochloride276

Quarterly reports (20042025)

20052010201520202025

An upward trend reflects increased FAERS reporting overall, not necessarily increased risk.

Taking mexiletine with another medication?

Ask OpenClaim about your specific drug combination. Get a sourced report using FDA data, drug labels, and medical literature.