Drug profile

The FDA adverse-event record for Hydroxyzine

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

982
adverse-event reports
3.9%
death-coded share
Dog
most-reported species
213
Emesis - 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.
982
Total Reports
38
Deaths Reported
3.9%
Death Rate

Active Ingredients

Hydroxyzine

Administration Routes

OralUnknownOphthalmic

Species Affected

Dog 950
Cat 15
Human 9
Unknown 5
Horse 3

Most Affected Breeds

Retriever - Labrador 94
Shih Tzu 51
Crossbred Canine/dog 49
Terrier - Yorkshire 44
Retriever - Golden 37
Boxer (German Boxer) 32
Terrier - West Highland White 31
Terrier (unspecified) 29
Shepherd Dog - German 28
Chihuahua 28

Most Reported Reactions

Emesis 213
Vomiting 166
Lethargy (see also Central nervous system depression in 'Neurological') 127
Diarrhoea 81
Other abnormal test result NOS 75
Lack of efficacy - NOS 74
Elevated serum alkaline phosphatase (SAP) 46
Elevated alanine aminotransferase (ALT) 42
Seizure NOS 41
Anorexia 41
Behavioural disorder NOS 41
Decreased appetite 37

Outcome Breakdown

Recovered/Normal
423 (43.3%)
Ongoing
309 (31.6%)
Outcome Unknown
170 (17.4%)
Recovered with Sequela
37 (3.8%)
Euthanized
20 (2.0%)
Died
18 (1.8%)

Hydroxyzine Adverse Event Insights

982 reports name Hydroxyzine; 38 recorded a death outcome (3.9% of reported events, not a population-level mortality rate). Active ingredient: Hydroxyzine. Administration routes: Oral, Unknown, Ophthalmic.

By species: Dog (950 reports), Cat (15 reports), Human (9 reports). By breed: Retriever - Labrador (94), Shih Tzu (51), Crossbred Canine/dog (49).

Leading clinical signs: Emesis (213), Vomiting (166), Lethargy (see also Central nervous system depression in 'Neurological') (127), Diarrhoea (81). Outcome, 977 coded reports: Recovered/Normal leads at 43.3%.

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.