Drug profile

The FDA adverse-event record for Cefalexin

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

16
adverse-event reports
6.3%
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.
16
Total Reports
1
Deaths Reported
6.3%
Death Rate

Active Ingredients

Cefalexin

Administration Routes

UnknownOral

Species Affected

Dog 14
Human 1
Cat 1

Most Affected Breeds

Spaniel - King Charles Cavalier 3
Boxer (German Boxer) 2
Siberian Husky 2
Terrier - Yorkshire 1
American Pit Bull Terrier 1
Unknown 1
Doberman Pinscher 1
Terrier - Boston 1
Bulldog 1
Domestic (unspecified) 1

Most Reported Reactions

Vomiting 3
Ataxia 3
Cough 3
Congestive heart failure 3
Emesis 2
Lethargy (see also Central nervous system depression in 'Neurological') 2
Unable to stand 2
Walking difficulty 2
Sensory abnormality NOS 2
Hypermetria 2
Proprioception abnormality 2
Surgical site disorder 2

Outcome Breakdown

Outcome Unknown
9 (56.3%)
Recovered/Normal
4 (25.0%)
Ongoing
2 (12.5%)
Died
1 (6.3%)

Cefalexin Adverse Event Insights

16 reports name Cefalexin; 1 recorded a death outcome (6.3% of reported events, not a population-level mortality rate). Active ingredient: Cefalexin. Administration routes: Unknown, Oral.

By species: Dog (14 reports), Human (1 reports), Cat (1 reports). By breed: Spaniel - King Charles Cavalier (3), Boxer (German Boxer) (2), Siberian Husky (2).

Leading clinical signs: Vomiting (3), Ataxia (3), Cough (3), Congestive heart failure (3). Outcome, 16 coded reports: Outcome Unknown leads at 56.3%.

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.