Drug profile

The FDA adverse-event record for Sulfadimethoxine

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

742
adverse-event reports
10.4%
death-coded share
Dog
most-reported species
103
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.
742
Total Reports
77
Deaths Reported
10.4%
Death Rate

Active Ingredients

Sulfadimethoxine

Administration Routes

OralUnknownSubcutaneousTopicalIntramuscularIntravenousRectalOphthalmic

Species Affected

Dog 458
Unknown 128
Cat 119
Cattle 30
Human 3
Rabbit 3
Sheep 1

Most Affected Breeds

Unknown 131
Retriever - Labrador 56
Domestic Shorthair 55
Retriever - Golden 33
Dog (unknown) 26
Crossbred Canine/dog 22
Chihuahua 21
Shepherd Dog - German 20
Boxer (German Boxer) 17
Shepherd Dog - Australian 15

Most Reported Reactions

Vomiting 103
Lethargy (see also Central nervous system depression in 'Neurological') 96
Diarrhoea 87
Lack of efficacy (protozoa) - Coccidia 78
Death 50
Anorexia 47
Other abnormal test result NOS 39
Emesis 33
Uncoded sign 31
Ataxia 29
Fever 27
Anaemia NOS 27

Outcome Breakdown

Ongoing
196 (35.2%)
Outcome Unknown
142 (25.5%)
Recovered/Normal
134 (24.1%)
Died
60 (10.8%)
Euthanized
17 (3.1%)
Recovered with Sequela
8 (1.4%)

Sulfadimethoxine Adverse Event Insights

742 reports name Sulfadimethoxine; 77 recorded a death outcome (10.4% of reported events, not a population-level mortality rate). Active ingredient: Sulfadimethoxine. Administration routes: Oral, Unknown, Subcutaneous, Topical.

By species: Dog (458 reports), Unknown (128 reports), Cat (119 reports). By breed: Unknown (131), Retriever - Labrador (56), Domestic Shorthair (55).

Leading clinical signs: Vomiting (103), Lethargy (see also Central nervous system depression in 'Neurological') (96), Diarrhoea (87), Lack of efficacy (protozoa) - Coccidia (78). Outcome, 557 coded reports: Ongoing leads at 35.2%.

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.