Drug profile

The FDA adverse-event record for Sulfamethazine

35 adverse-event reports submitted to the FDA Center for Veterinary Medicine reference Sulfamethazine. Species, reactions, and outcomes follow.

#1340 of 2,679
by report volume (all drugs)
35
adverse-event reports
28.6%
death-coded share
Unknown
most-reported species
Verify with FDA CVM →

Corpus placement

According to the FDA Center for Veterinary Medicine openFDA adverse-event extract, Sulfamethazine ranks #1331 of 2679 by total reports (35). Death-coded-share rank requires at least 50 reports. National dual: Milbemycin Oxime + Spinosad is #1 of 2679 drugs by total adverse-event reports (149,624) at death-coded-share rank 965 of 1130 drugs with at least 50 reports (2.3%); separately, Atlantic Salmon Transgenic Whole (Opafp-Ghc2 Rdna Construct Inserted Into The A-Locus In The Eo-1A Lineage) is #1 highest death-coded share at 97.8% (report rank #821).

149,624
Milbemycin Oxime + Spinosad reports (#1)
97.8%
Atlantic Salmon Transgenic Whole (Opafp-Ghc2 Rdna Construct Inserted Into The A-Locus In The Eo-1A Lineage) death share (#1)
#1331
This drug, reports of 2679

Report volume reflects how common a breed or drug is and how often owners and vets file — not actual risk. Death-coded share ranks are limited to entries with enough reports to be meaningful. The two maps do not agree at #1.

Release-over-release change

What changed in the latest FDA data snapshot

PlainBreed reconstructed the prior snapshot from dated openFDA partitions through 2025 Q4, then compared it with the 2026-07-27 openFDA export. Sulfamethazine has 35 reports now versus 35 in that prior snapshot: 0 the same number of (0.0%).

Report change
+0
Death-coded reports
+0
Death-coded share
+0.0 pts

This compares reported-event counts in two source snapshots. It does not establish a change in real-world risk, product safety, or disease incidence.

Subscribe to Sulfamethazine changes

Signature read: Sulfamethazine's 28.6% death-coded share is among the highest in the openFDA drug corpus.

Important: Adverse event reports do not establish that a drug caused or contributed to the event. Consult your veterinarian before making treatment decisions.
35
Total Reports
10
Deaths Reported
28.6%
Death-coded share of reports

Active Ingredients

Sulfamethazine

Administration Routes

UnknownOral

Species Affected

Unknown 18
Chicken 5
Cattle 5
Other Birds 4
Goat 1
Human 1
Dog 1

Most Affected Breeds

Unknown 19
Chicken (unknown) 4
Other Birds (unknown) 4
Mixed (Cattle) 2
Crossbred Caprine/goat 1
Retriever - Labrador 1
Holstein-Friesian also known as Holstein 1
Jersey 1
Red Angus 1
Leghorn 1

Most Reported Reactions

Death 9
Color, Abnormal 3
Vials, Leaking 3
Product Defect, General 2
Solution, Abnormal 2
Caps, Abnormal 2
Respiratory distress 2
Diarrhoea 1
Lack of efficacy (protozoa) - Coccidia 1
Containers, Damaged 1
UNPALATABLE 1
Granules/Powder, Abnormal 1

Outcome Breakdown

Died
9 (50.0%)
Recovered/Normal
4 (22.2%)
Outcome Unknown
3 (16.7%)
Recovered with Sequela
1 (5.6%)
Euthanized
1 (5.6%)

Sulfamethazine: high death-coded share in the FDA AER row

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.

What to do with this drug

A report does not prove a drug caused the reaction; consult a veterinarian before acting on this data.

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

openFDA Animal & Veterinary Adverse Events (FDA CVM) for Sulfamethazine (#1340 of 2,679 by report volume); death-coded 28.6%. PlainBreed drug row · death-coded share stamp 28.6% · vintage 2025.

Informational only. FDA adverse-event reports are voluntary and do not prove causation; consult a veterinarian before acting on them. Verify with FDA CVM →