Phenobarbital — FDA Animal & Veterinary Adverse Event (ADE) Reports
Source: openFDA animalandveterinary/event.json, the FDA Center for Veterinary Medicine (CVM) adverse event report database. Data pulled 2026-07-21. Counts are report-level: one report may list multiple reactions and multiple animals, so figures are not additive and do not imply causation. Phenobarbital is a anticonvulsant (canine epilepsy).
Total reports
Phenobarbital: 1645
Reports by species (top entries)
- Dog 1514
- Cat 124
- 1
- Other Canids 1
Top reported reactions (VEDDRA terms, top entries)
- Seizure NOS 614
- Lethargy (see also Central nervous system depression in 'Neurological') 181
- Vomiting 165
- Death by euthanasia 120
- Other abnormal test result NOS 104
- Ataxia 98
- Lack of efficacy - NOS 95
- Emesis 94
- Diarrhoea 88
- Death 82
"Lack of efficacy" terms denote product-performance reports, not adverse reactions.
Source JSON: pdf-raw/ade/ade_active_ingredients_2026-07-21.json (openFDA animalandveterinary/event.json, pulled 2026-07-21).