Drug profile

The FDA adverse-event record for Hydroxyzine

1,003 FDA reports name Hydroxyzine, a high-volume drug in the CVM extract. Species, reactions, and outcomes follow.

#180 of 2,679
by report volume (all drugs)
1,003
adverse-event reports
4.0%
death-coded share
Dog
most-reported species

Corpus placement

According to the FDA Center for Veterinary Medicine openFDA adverse-event extract, Hydroxyzine ranks #180 of 2679 by total reports (1,003) and #847 of 1130 by death-coded share (4.0%). 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)
#180
This drug, reports of 2679
#847
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. Hydroxyzine has 1,003 reports now versus 999 in that prior snapshot: 4 more (0.4%).

Report change
+4
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 Hydroxyzine changes

Signature read: 1,003 reports place Hydroxyzine in the upper third of FDA AER volume (#180 of 2,679).

Important: Adverse event reports do not establish that a drug caused or contributed to the event. Consult your veterinarian before making treatment decisions.
1,003
Total Reports
40
Deaths Reported
4.0%
Death-coded share of reports

Active Ingredients

Hydroxyzine

Administration Routes

OralUnknownOphthalmic

Species Affected

Dog 970
Cat 16
Human 9
Unknown 5
Horse 3

Most Affected Breeds

Retriever - Labrador 95
Shih Tzu 51
Crossbred Canine/dog 49
Terrier - Yorkshire 44
Retriever - Golden 37
Boxer (German Boxer) 34
Terrier - West Highland White 31
Terrier (unspecified) 31
Shepherd Dog - German 29
Chihuahua 28

Most Reported Reactions

Emesis 213
Vomiting 170
Lethargy (see also Central nervous system depression in 'Neurological') 127
Diarrhoea 86
Other abnormal test result NOS 79
Lack of efficacy - NOS 77
Elevated serum alkaline phosphatase (SAP) 46
Seizure NOS 42
Behavioural disorder NOS 42
Elevated alanine aminotransferase (ALT) 42
Anorexia 41
Decreased appetite 37

Outcome Breakdown

Recovered/Normal
424 (42.5%)
Ongoing
319 (32.0%)
Outcome Unknown
178 (17.8%)
Recovered with Sequela
37 (3.7%)
Euthanized
22 (2.2%)
Died
18 (1.8%)

Hydroxyzine: low 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.

High-volume nationwide drug peers

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

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 Hydroxyzine (#180 of 2,679 by report volume); death-coded 4.0%. PlainBreed drug row · report volume stamp 1,003 · 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 →