Drug profile

The FDA adverse-event record for Hydroxyzine Hcl

44 adverse-event reports submitted to the FDA Center for Veterinary Medicine reference Hydroxyzine Hcl. Species, reactions, and outcomes follow.

#1205 of 2,679
by report volume (all drugs)
44
adverse-event reports
6.8%
death-coded share
Dog
most-reported species
Verify with FDA CVM →

Corpus placement

According to the FDA Center for Veterinary Medicine openFDA adverse-event extract, Hydroxyzine Hcl ranks #1198 of 2679 by total reports (44). Death-coded-share rank requires at least 50 reports. 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)
#1198
This drug, reports of 2679

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 Hcl has 44 reports now versus 44 in that prior snapshot: 0 the same number of (0.0%).

Report change
+0
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 Hcl changes

Signature read: death-coded share at 6.8% is the most distinctive stamp on Hydroxyzine Hcl's FDA AER row.

Important: Adverse event reports do not establish that a drug caused or contributed to the event. Consult your veterinarian before making treatment decisions.
44
Total Reports
3
Deaths Reported
6.8%
Death-coded share of reports

Active Ingredients

Hydroxyzine Hcl

Administration Routes

OralUnknown

Species Affected

Dog 44

Most Affected Breeds

Shih Tzu 6
Pug 5
Retriever - Labrador 5
Spaniel - Cocker American 2
Terrier (unspecified) 2
Retriever (unspecified) 1
Bichon Frise 1
Terrier - Irish Soft-coated Wheaten 1
Schnauzer - Miniature 1
Pit Bull 1

Most Reported Reactions

Emesis 18
Lack of efficacy (ectoparasite) - flea 6
Lethargy (see also Central nervous system depression in 'Neurological') 5
Vomiting 5
Decreased appetite 4
Diarrhoea 4
Lack of efficacy - NOS 3
UNPALATABLE 2
Reluctant to move 2
Dullness 2
Behavioural disorder NOS 2
Pale mucous membrane 1

Outcome Breakdown

Recovered/Normal
22 (50.0%)
Outcome Unknown
10 (22.7%)
Ongoing
5 (11.4%)
Recovered with Sequela
4 (9.1%)
Died
2 (4.5%)
Euthanized
1 (2.3%)

Hydroxyzine Hcl Adverse Event Insights

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.

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 Hcl (#1205 of 2,679 by report volume); death-coded 6.8%. PlainBreed drug row · death-coded share stamp 6.8% · 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 →