Doxycycline — 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. Doxycycline is a veterinary active ingredient.
Total reports
Doxycycline: 4320
Reports by species (top entries)
- Dog 3870
- Cat 251
- Horse 14
- Human 7
Top reported reactions (VEDDRA terms, top entries)
- Lack of efficacy (endoparasite) - heartworm 1194
- Vomiting 602
- Lethargy (see also Central nervous system depression in 'Neurological') 468
- Other abnormal test result NOS 357
- Death by euthanasia 330
- Anorexia 313
- Elevated alanine aminotransferase (ALT) 284
- Diarrhoea 269
- Lack of efficacy - NOS 264
- Death 241
"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).