Praziquantel — 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. Praziquantel is a veterinary active ingredient.
Total reports
Praziquantel: 79254
Reports by species (top entries)
- Dog 57958
- Cat 12261
- Horse 3005
- Human 315
- Donkey 26
- Other 8
Top reported reactions (VEDDRA terms, top entries)
- Vomiting 17258
- Lack of efficacy (endoparasite) - heartworm 8780
- Diarrhoea 6274
- Lethargy (see also Central nervous system depression in 'Neurological') 5215
- Lack of efficacy (endoparasite) - hookworm 4130
- INEFFECTIVE, HOOKS 3123
- Lack of efficacy (endoparasite) - tapeworm 2803
- Hypersalivation 2449
- Ataxia 2353
- Other abnormal test result NOS 2306
"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).