Drug profile

The FDA adverse-event record for Praziquantel

3,343 adverse-event reports submitted to the FDA Center for Veterinary Medicine reference Praziquantel. See the species affected, top reactions, and outcomes below.

3,343
adverse-event reports
3.1%
death-coded share
Cat
most-reported species
592
Lack of efficacy (endoparasite) - tapeworm - top reaction
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Important: Adverse event reports do not establish that a drug caused or contributed to the event. Consult your veterinarian before making treatment decisions.
3,343
Total Reports
103
Deaths Reported
3.1%
Death Rate

Active Ingredients

Praziquantel

Administration Routes

OralUnknownSubcutaneousParenteralIntramuscularTopicalOtherOphthalmicSubconjunctivalIntraocular

Species Affected

Cat 1,469
Unknown 958
Dog 883
Human 28
Other 2
Cockatiel 1
Chinchilla 1
Chicken 1

Most Affected Breeds

Unknown 990
Domestic Shorthair 689
Cat (unknown) 447
Domestic Longhair 123
Dog (unknown) 91
Retriever - Labrador 72
Chihuahua 61
Domestic Mediumhair 58
Crossbred Canine/dog 55
Siamese 41

Most Reported Reactions

Lack of efficacy (endoparasite) - tapeworm 592
Vomiting 314
Product label issues 278
Underfilling, Bottles 251
Lethargy (see also Central nervous system depression in 'Neurological') 249
Tablets, Abnormal 202
Diarrhoea 195
Emesis 195
Patient instructions for use on label confusing 169
Behavioural disorder NOS 165
Product Defect, General 155
Anorexia 136

Outcome Breakdown

Outcome Unknown
1,353 (57.5%)
Recovered/Normal
644 (27.4%)
Ongoing
246 (10.5%)
Died
80 (3.4%)
Euthanized
23 (1.0%)
Recovered with Sequela
6 (0.3%)

Praziquantel Adverse Event Insights

3,343 reports name Praziquantel; 103 recorded a death outcome (3.1% of reported events, not a population-level mortality rate). Active ingredient: Praziquantel. Administration routes: Oral, Unknown, Subcutaneous, Parenteral.

By species: Cat (1,469 reports), Unknown (958 reports), Dog (883 reports). By breed: Unknown (990), Domestic Shorthair (689), Cat (unknown) (447).

Leading clinical signs: Lack of efficacy (endoparasite) - tapeworm (592), Vomiting (314), Product label issues (278), Underfilling, Bottles (251). Outcome, 2,352 coded reports: Outcome Unknown leads at 57.5%.

Read these counts as reporting volume, not risk: per our methodology, a widely-prescribed drug will rack up more raw FDA reports in a given year than a rarely-used one at an identical true rate, so we recommend comparing within similar-exposure products rather than across the full 2025 catalog.

Source: FDA Center for Veterinary Medicine openFDA Animal & Veterinary Adverse Events (CVM AER) · 2025

Every figure on PlainBreed is rendered directly from FDA openFDA adverse event data, no number is typed in by an editor. This page draws directly on FDA openFDA data, no figure is typed in by an editor. See our editorial standards & corrections policy, the methodology behind these numbers, or report a data error.