Reaction profile

The FDA adverse-event record for mammary hyperplasia

44 FDA adverse-event reports reference mammary hyperplasia (VeDDRA 530). See the species, breeds, and drugs most associated with it below.

44
reports citing this reaction
4.5%
death-coded share
Dog
most-affected species
Estriol Tablets
most-associated drug
Verify with FDA CVM →
44
Total Reports
2
Deaths
4.5%
Death Rate

Species Most Affected

Dog 30
Cattle 12
Cat 1
Horse 1

Breeds Most Affected

Crossbred Canine/dog 7
Mixed (Cattle) 6
Terrier - Yorkshire 4
Shepherd Dog - Australian 2
Holstein-Friesian also known as Holstein 2
Domestic (unspecified) 1
Cattle (other) 1
Shepherd Dog - German 1
Pit Bull 1
Beagle 1

Associated Drugs

Estriol Tablets 19
Testosterone Propionate;Estradiol Benzoate 5
Estriol 3
Trilostane 3
Cyclosporine 2
Estradiol Benzoate; Testosterone Propionate 2
Melengestrol Acetate 2
Estradiol 2
Trenbolone Acetate;Estradiol Benzoate 2
Milbemycin Oxime + Spinosad 1
Cyclosporine A 1
Spinosad 1
Heartworm Preventative 1
Hypoallergenic Diet 1
Tacrolimus 1
Oclacitinib Maleate 1
Terbinafine Hcl 1
Marbofloxacin 1
Trenbolone; Estradiol; Tylosin Tartrate 1
Ivermectin + Pyrantel As Pamoate Salt 1

Mammary hyperplasia Reaction Insights

44 reports name Mammary hyperplasia; 2 recorded a death outcome (4.5% of reported events, not a population-level mortality rate). VeDDRA code: 530.

By species: Dog (30 reports), Cattle (12 reports), Cat (1 reports). By breed: Crossbred Canine/dog (7), Mixed (Cattle) (6), Terrier - Yorkshire (4).

Most co-reported drugs: Estriol Tablets (19 reports), Testosterone Propionate;Estradiol Benzoate (5 reports), Estriol (3 reports), Trilostane (3 reports).

Read these counts as reporting volume, not risk: per our methodology, co-reporting reflects temporal association captured in voluntary submissions, not proof that a drug caused this reaction. A widely-prescribed drug will rack up more raw co-reports at an identical true rate than a rarely-used one, so compare within similar-exposure products.

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.