Vitamin B12 — 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 2026-07-22. Counts are report-level: one report may list multiple reactions and multiple animals, so figures are not additive and do not imply causation. Vitamin B12 is a active ingredient.
Total reports
Vitamin B12: 721
Reports by species (top entries)
- Cat 350
- Dog 350
- Human 14
- Pig 3
- Cattle 2
- Horse 1
Top reported reactions (VEDDRA terms, top entries)
- Vomiting 148
- Diarrhoea 109
- Lethargy (see also Central nervous system depression in 'Neurological') 103
- Weight loss 100
- Anorexia 92
- Death by euthanasia 91
- Lethargy (see also Central nervous system depression in Neurological) 82
- Not eating 79
- Other abnormal test result NOS 77
- Lack of efficacy - NOS 75
Source JSON: pdf-raw/ade/ade_active_ingredients_2026-07-22_b12.json (openFDA animalandveterinary/event.json, pulled 2026-07-22).