Ingredients

Ingredient sets that include praziquantel

Ordered by report count. FDA states that these data "cannot be used to estimate the risk associated with the product or compare one drug or device product with another"; counts follow sales volume and years on the market. A report can list more than one set, so shares can add to more than 100%.

Signs listed in reports, pooled

share of praziquantel reports listing the termall reports in the database

1. Vomiting21.3%17,728
2. Lack of efficacy (endoparasite) - heartworm[the product did not have the expected effect: heartworm]12%9,981
3. Lethargy[unusually tired or inactive]8.5%7,095
4. Diarrhoea[diarrhea]7.7%6,437
5. Lack of efficacy (endoparasite) - hookworm[the product did not have the expected effect: hookworms]5.7%4,782
6. Ineffective, hooks[legacy FDA term: the product did not have the expected effect (hooks)]3.8%3,170
7. Lack of efficacy (endoparasite) - tapeworm[the product did not have the expected effect: tapeworms]3.6%2,970
8. Hypersalivation[drooling]3%2,461
9. Ataxia[unsteady, uncoordinated movement]2.9%2,400
10. Other abnormal test result NOS[abnormal laboratory result, type not specified]2.8%2,315
11. Anorexia[not eating]2.7%2,240
12. Behavioural disorder NOS[behaviour change, type not specified]2.7%2,209
13. Unpalatable[legacy FDA term: the animal would not take it]2.6%2,191
14. Ineffective, heartworm larvae[legacy FDA term: the product did not have the expected effect (heartworm larvae)]2.6%2,175
15. Lack of efficacy (endoparasite) - roundworm NOS[the product did not have the expected effect: roundworms]2.5%2,107
16. Emesis (multiple)[vomiting more than once]2.3%1,895
17. Not eating2.2%1,835
18. Emesis[vomiting]2.2%1,817
19. Seizure NOS[seizure, type not specified]2.1%1,750
20. Death1.9%1,613
21. Application site alopecia[hair loss where the product was applied]1.8%1,507
22. Lack of efficacy - NOS[the product did not have the expected effect]1.7%1,420
23. Lack of efficacy (roundworm)[the product did not have the expected effect: roundworms]1.6%1,308
24. Overdose[more than the labelled amount was given]1.4%1,184
25. Decreased appetite1.4%1,131
26. Depression[dull, quiet or withdrawn]1.3%1,087
27. Loose stool1.3%1,084
28. Weight loss1.3%1,082
29. Accidental exposure[exposure that was not intended]1.2%1,010
30. Shaking1.2%989

Pooled across every ingredient set and every report that names the ingredient. One report can list several terms and several drugs; a term here may relate to any of them or to none.

Monthly reports by species, five years

By month of receipt; each panel has its own scale. The newest months are incomplete because FDA posts reports with a delay of three to six months.

Outcomes, report types and ages

Coloured bar: reports naming praziquantel. Grey bar: all 1,357,245 reports. Outcomes are as stated by the reporter; FDA has not necessarily determined whether any product played a part.

In context

Shares of reports, not of animals treated: how many animals receive the ingredient is not public. Ingredients used in anaesthesia, cancer care or in old animals carry more serious outcomes in their reports for that reason alone.

Where this comes from. Counts are built from the openFDA Animal & Veterinary adverse event bulk files released 28 Sep 2026, which hold reports FDA's Center for Veterinary Medicine received through 31 Mar 2026. openFDA masks brand and manufacturer names in these files, so drugs are counted by the active ingredients each record discloses and no figure is attributed to a brand, application or company. Ingredient names, and the separate reference lists of approved products, follow the FDA Green Book as of 30 Sep 2026. Ingredient names follow the Green Book; salts and forms are kept as FDA lists them. Drug entries are matched by the active ingredients their unmasked ingredient field discloses. No report text, lot numbers or reporter details are published. See the methodology and sources; FDA's record is authoritative, and corrections are handled within five working days.