Drug profile

The FDA adverse-event record for Pentobarbital Sodium + Phenytoin Sodium

288 adverse-event reports submitted to the FDA Center for Veterinary Medicine reference Pentobarbital Sodium + Phenytoin Sodium. See the species affected, top reactions, and outcomes below.

288
adverse-event reports
79.2%
death-coded share
Dog
most-reported species
137
INEFFECTIVE, EUTHANASIA - 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.
288
Total Reports
228
Deaths Reported
79.2%
Death Rate

Active Ingredients

Pentobarbital SodiumPentobarbital Sodium + Phenytoin SodiumPhenytoin Sodium

Administration Routes

IntravenousUnknownSubcutaneousTopicalIntracardiacOphthalmicOralParenteralIntraperitonealOther

Species Affected

Dog 159
Cat 40
Unknown 37
Horse 31
Human 10
Other 4
Goat 2
Other Mammals 1
Pig 1
Chicken 1

Most Affected Breeds

Unknown 87
Dog (unknown) 31
Domestic Shorthair 19
Cat (unknown) 14
Retriever - Labrador 11
Chihuahua 10
Horse (unknown) 9
Mixed (Dog) 8
Pit Bull 6
Rottweiler 5

Most Reported Reactions

INEFFECTIVE, EUTHANASIA 137
Lack of efficacy - NOS 81
INEFFECTIVE, DELAYED EFFECT 34
Overdose 18
Death by euthanasia 17
Vocalisation 15
Agonal breathing 12
Appearance, Abnormal 11
Product Defect, General 9
Stopper, abnormal 9
Partial lack of efficacy 8
Drug administration error 8

Outcome Breakdown

Euthanized
224 (89.2%)
Recovered/Normal
17 (6.8%)
Outcome Unknown
6 (2.4%)
Died
4 (1.6%)

Pentobarbital Sodium + Phenytoin Sodium Adverse Event Insights

288 reports name Pentobarbital Sodium + Phenytoin Sodium; 228 recorded a death outcome (79.2% of reported events, not a population-level mortality rate). Active ingredients: Pentobarbital Sodium, Pentobarbital Sodium + Phenytoin Sodium, Phenytoin Sodium. Administration routes: Intravenous, Unknown, Subcutaneous, Topical.

By species: Dog (159 reports), Cat (40 reports), Unknown (37 reports). By breed: Unknown (87), Dog (unknown) (31), Domestic Shorthair (19).

Leading clinical signs: INEFFECTIVE, EUTHANASIA (137), Lack of efficacy - NOS (81), INEFFECTIVE, DELAYED EFFECT (34), Overdose (18). Outcome, 251 coded reports: Euthanized leads at 89.2%.

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.