Drug profile

The FDA adverse-event record for Zilpaterol

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

#951 of 2,679
by report volume (all drugs)
68
adverse-event reports
72.1%
death-coded share
Cattle
most-reported species

Corpus placement

According to the FDA Center for Veterinary Medicine openFDA adverse-event extract, Zilpaterol ranks #942 of 2679 by total reports (68) and #31 of 1130 by death-coded share (72.1%). 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)
#942
This drug, reports of 2679
#31
This drug, death share of 1130

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. Zilpaterol has 68 reports now versus 68 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 Zilpaterol changes

Signature read: Zilpaterol's 72.1% 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.
68
Total Reports
49
Deaths Reported
72.1%
Death-coded share of reports

Active Ingredients

Zilpaterol

Administration Routes

OralUnknownRespiratory (Inhalation)

Species Affected

Cattle 57
Horse 5
Human 2
Unknown 2
Sheep 1
Pig 1

Most Affected Breeds

Crossbred Bovine/Cattle 29
Cattle (unknown) 15
Holstein-Friesian also known as Holstein 5
Quarter Horse 4
Unknown 4
Aberdeen Angus 4
Horse (unknown) 1
Cattle (other) 1
Sheep (unknown) 1
Hereford pig 1

Most Reported Reactions

Death 29
Accidental exposure 8
Claw / hoof / nail disorder NOS 8
Pneumonia 7
Death by euthanasia 7
INEFFECTIVE, PRODUCTION (MEAT) 6
DEATH-SLAUGHTERED 6
Anorexia 5
INEFFECTIVE, WEIGHT INC 4
Recumbency 4
Hyperhidrosis 4
No sign 4

Outcome Breakdown

Died
49 (98.0%)
Recovered/Normal
1 (2.0%)

Zilpaterol: 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.

Nationwide drugs with similar profiles

Two openFDA-derived peer sets for Zilpaterol, both floored at ≥50 reports so the neighborhoods stay in the advertised mass.

Similar death-coded share

Nearest other drugs by death-coded share (72.1% here), distinct from the volume row.

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 Zilpaterol (#951 of 2,679 by report volume); death-coded 72.1%. PlainBreed drug row · death-coded share stamp 72.1% · 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 →