Drug profile

The FDA adverse-event record for Phenobarbitol

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

#1010 of 2,679
by report volume (all drugs)
61
adverse-event reports
23.0%
death-coded share
Dog
most-reported species

Corpus placement

According to the FDA Center for Veterinary Medicine openFDA adverse-event extract, Phenobarbitol ranks #1004 of 2679 by total reports (61) and #200 of 1130 by death-coded share (23.0%). 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)
#1004
This drug, reports of 2679
#200
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. Phenobarbitol has 61 reports now versus 60 in that prior snapshot: 1 more (1.7%).

Report change
+1
Death-coded reports
+0
Death-coded share
−0.4 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 Phenobarbitol changes

Signature read: Phenobarbitol's 23.0% death-coded share is among the highest in the openFDA drug corpus.

Important: Adverse event reports do not establish that a drug caused or contributed to the event. Consult your veterinarian before making treatment decisions.
61
Total Reports
14
Deaths Reported
23.0%
Death-coded share of reports

Active Ingredients

Phenobarbitol

Administration Routes

OralUnknownIntravenousTopicalOphthalmic

Species Affected

Dog 60
Cat 1

Most Affected Breeds

Crossbred Canine/dog 9
Retriever - Labrador 5
Chihuahua 4
Dachshund (unspecified) 4
Retriever - Golden 4
Terrier - Yorkshire 3
Shih Tzu 3
Bulldog - French 2
Bichon Frise 2
Collie - Border 2

Most Reported Reactions

Seizure NOS 25
Death by euthanasia 9
Ataxia 6
Lethargy (see also Central nervous system depression in 'Neurological') 5
Death 5
Unable to stand 4
Behavioural disorder NOS 4
Restlessness 3
Weakness 3
Inappetence 3
Diarrhoea 3
Elevated gamma-glutamyl transferase (GGT) 3

Outcome Breakdown

Outcome Unknown
20 (32.8%)
Recovered/Normal
17 (27.9%)
Euthanized
9 (14.8%)
Ongoing
9 (14.8%)
Died
5 (8.2%)
Recovered with Sequela
1 (1.6%)

Phenobarbitol: high 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.

Nationwide drugs with similar profiles

Two openFDA-derived peer sets for Phenobarbitol, 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 Phenobarbitol (#1010 of 2,679 by report volume); death-coded 23.0%. PlainBreed drug row · death-coded share stamp 23.0% · 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 →