Drug profile

The FDA adverse-event record for Mexiletine Hydrochloride

10 adverse-event reports submitted to the FDA Center for Veterinary Medicine reference Mexiletine Hydrochloride. See the species affected, top reactions, and outcomes below.

10
adverse-event reports
10.0%
death-coded share
Dog
most-reported species
3
Vomiting - top reaction
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Important: Adverse event reports do not establish that a drug caused or contributed to the event. Consult your veterinarian before making treatment decisions.
10
Total Reports
1
Deaths Reported
10.0%
Death Rate

Active Ingredients

Mexiletine Hydrochloride

Administration Routes

OralUnknown

Species Affected

Dog 10

Most Affected Breeds

Boxer (German Boxer) 6
Pit Bull 1
Terrier - Bull - Staffordshire 1
Shepherd Dog - German 1
Pointer - English Pointer 1

Most Reported Reactions

Vomiting 3
Diarrhoea 2
Elevated alanine aminotransferase (ALT) 2
Elevated serum alkaline phosphatase (SAP) 2
Cardiomyopathy 2
Arrhythmia 2
Not eating 1
Lethargy (see also Central nervous system depression in 'Neurological') 1
Tense abdomen 1
Abnormal radiograph finding 1
Spondylosis 1
Heart murmur 1

Outcome Breakdown

Ongoing
5 (50.0%)
Recovered/Normal
2 (20.0%)
Outcome Unknown
2 (20.0%)
Died
1 (10.0%)

Mexiletine Hydrochloride Adverse Event Insights

10 reports name Mexiletine Hydrochloride; 1 recorded a death outcome (10.0% of reported events, not a population-level mortality rate). Active ingredient: Mexiletine Hydrochloride. Administration routes: Oral, Unknown.

By species: Dog (10 reports). By breed: Boxer (German Boxer) (6), Pit Bull (1), Terrier - Bull - Staffordshire (1).

Leading clinical signs: Vomiting (3), Diarrhoea (2), Elevated alanine aminotransferase (ALT) (2), Elevated serum alkaline phosphatase (SAP) (2). Outcome, 10 coded reports: Ongoing leads at 50.0%.

Read these counts as reporting volume, not risk: per our methodology, a widely-prescribed drug will rack up more raw FDA reports in a given year than a rarely-used one at an identical true rate, so we recommend comparing within similar-exposure products rather than across the full 2025 catalog.

Source: FDA Center for Veterinary Medicine openFDA Animal & Veterinary Adverse Events (CVM AER) · 2025

Every figure on PlainBreed is rendered directly from FDA openFDA adverse event data, no number is typed in by an editor. This page draws directly on FDA openFDA data, no figure is typed in by an editor. See our editorial standards & corrections policy, the methodology behind these numbers, or report a data error.