Drug profile

The FDA adverse-event record for Estriol

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

622
adverse-event reports
6.8%
death-coded share
Dog
most-reported species
257
Lack of efficacy - NOS - 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.
622
Total Reports
42
Deaths Reported
6.8%
Death Rate

Active Ingredients

Estriol

Administration Routes

OralUnknown

Species Affected

Dog 621
Rat 1

Most Affected Breeds

Crossbred Canine/dog 103
Retriever - Labrador 62
Doberman Pinscher 27
Shepherd Dog - German 24
Dog (unknown) 24
Boxer (German Boxer) 18
Poodle (unspecified) 15
Siberian Husky 14
Schnauzer (unspecified) 13
Pit Bull 13

Most Reported Reactions

Lack of efficacy - NOS 257
Vaginal swelling 82
Vomiting 54
Anorexia 41
Death by euthanasia 37
Diarrhoea 30
Urinary tract infection 26
Weight loss 21
Polydipsia 20
Lethargy (see also Central nervous system depression in 'Neurological') 20
Seizure NOS 19
Vulvitis 17

Outcome Breakdown

Ongoing
81 (32.5%)
Recovered/Normal
65 (26.1%)
Outcome Unknown
60 (24.1%)
Died
26 (10.4%)
Euthanized
16 (6.4%)
Recovered with Sequela
1 (0.4%)

Estriol Adverse Event Insights

622 reports name Estriol; 42 recorded a death outcome (6.8% of reported events, not a population-level mortality rate). Active ingredient: Estriol. Administration routes: Oral, Unknown.

By species: Dog (621 reports), Rat (1 reports). By breed: Crossbred Canine/dog (103), Retriever - Labrador (62), Doberman Pinscher (27).

Leading clinical signs: Lack of efficacy - NOS (257), Vaginal swelling (82), Vomiting (54), Anorexia (41). Outcome, 249 coded reports: Ongoing leads at 32.5%.

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.