Zeranol Implant

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102 adverse event reports submitted to the FDA

Important: Adverse event reports do not establish that a drug caused or contributed to the event. Consult your veterinarian before making treatment decisions.
102
Total Reports
34
Deaths Reported
3330.0%
Death Rate

Active Ingredients

Zeranol Implant

Administration Routes

UnknownSubcutaneousParenteralOther

Species Affected

Cattle 52
Unknown 44
Human 6

Most Affected Breeds

Unknown 50
Cattle (other) 22
Aberdeen Angus 11
Crossbred Bovine/Cattle 10
Red Angus 4
Holstein-Friesian also known as Holstein 2
Cattle (unknown) 1
Charolais 1
Cattle (unspecified) 1

Most Reported Reactions

Death 30
Lack of efficacy - NOS 18
Product problem 17
Uncoded sign 16
Device Defective NOS 15
Product Defect, General 12
Dispenser, Abnormal 9
Lack of efficacy (bacteria) - NOS 7
Containers, Damaged 6
Difficulty of Use 6
Implant, Abnormal 5
Lateral recumbency 4

Outcome Breakdown

Died
33 (37.9%)
Ongoing
20 (23.0%)
Outcome Unknown
17 (19.5%)
Recovered/Normal
13 (14.9%)
Euthanized
3 (3.4%)
Recovered with Sequela
1 (1.1%)

Data Summary

Metric Value
Total adverse event reports 102
Reports involving death 34
Case-fatality rate (reported events) 3330.0%
Distinct species in reports 3
Distinct breeds in reports 9
Distinct reactions reported 20
Active ingredients on file 1

Source: FDA Center for Veterinary Medicine — Adverse Event Reporting (CVM AER). Counts reflect voluntary reports only.

Zeranol Implant Adverse Event Insights

The FDA Center for Veterinary Medicine database currently holds 102 adverse event reports referencing Zeranol Implant, including 34 reports in which the animal died — a 3330.0% case-fatality figure among reported events only, not a population-level mortality rate. Active ingredient on file: Zeranol Implant. Reported administration routes include Unknown, Subcutaneous, Parenteral, Other. These numbers reflect voluntary submissions from pet owners, veterinarians, and manufacturers and therefore under-represent mild events and over-represent severe ones — a pattern the FDA has documented repeatedly for pharmacovigilance datasets.

The species most frequently named in Zeranol Implant reports are Cattle (52 reports), Unknown (44 reports), Human (6 reports), with Cattle accounting for the largest share. Within those species, Unknown (50), Cattle (other) (22), Aberdeen Angus (11) appear most often — though breed popularity and ownership density shape these counts as much as any drug-specific sensitivity. This distribution matters because the same active ingredient can behave very differently across body sizes, ages, and species physiology.

The most commonly reported clinical signs associated with Zeranol Implant are Death (30), Lack of efficacy - NOS (18), Product problem (17), Uncoded sign (16). Of the 87 reports with a coded outcome, Died is the leading category at 37.9%. Because FDA adverse event data describes correlation rather than causation, these figures are best used to frame informed questions with a veterinarian and to compare reporting patterns across related products — not as a standalone safety verdict on Zeranol Implant.

Source: FDA Center for Veterinary Medicine — Adverse Event Reports FDA Center for Veterinary Medicine — Adverse Event Reports Data reflects voluntary submissions and may not represent actual incidence rates

Related

Data sourced from official AKC, AVMA, ACVO, and breed-club veterinary references. See our methodology for details. Retrieved and formatted by PlainBreed Editorial