Drug profile

The FDA adverse-event record for Praziquantel

3,498 FDA reports name Praziquantel, a high-volume drug in the CVM extract. Species, reactions, and outcomes follow.

#70 of 2,679
by report volume (all drugs)
3,498
adverse-event reports
3.0%
death-coded share
Cat
most-reported species

Corpus placement

According to the FDA Center for Veterinary Medicine openFDA adverse-event extract, Praziquantel ranks #70 of 2679 by total reports (3,498) and #911 of 1130 by death-coded share (3.0%). National dual: Milbemycin Oxime + Spinosad is #1 of 2679 drugs by total adverse-event reports (149,624) at death-coded-share rank 965 of 1130 drugs with at least 50 reports (2.3%); separately, Atlantic Salmon Transgenic Whole (Opafp-Ghc2 Rdna Construct Inserted Into The A-Locus In The Eo-1A Lineage) is #1 highest death-coded share at 97.8% (report rank #821).

149,624
Milbemycin Oxime + Spinosad reports (#1)
97.8%
Atlantic Salmon Transgenic Whole (Opafp-Ghc2 Rdna Construct Inserted Into The A-Locus In The Eo-1A Lineage) death share (#1)
#70
This drug, reports of 2679
#911
This drug, death share of 1130

Report volume reflects how common a breed or drug is and how often owners and vets file — not actual risk. Death-coded share ranks are limited to entries with enough reports to be meaningful. The two maps do not agree at #1.

Release-over-release change

What changed in the latest FDA data snapshot

PlainBreed reconstructed the prior snapshot from dated openFDA partitions through 2025 Q4, then compared it with the 2026-07-27 openFDA export. Praziquantel has 3,498 reports now versus 3,432 in that prior snapshot: 66 more (1.9%).

Report change
+66
Death-coded reports
+0
Death-coded share
−0.1 pts

This compares reported-event counts in two source snapshots. It does not establish a change in real-world risk, product safety, or disease incidence.

Subscribe to Praziquantel changes

Signature read: 3,498 reports place Praziquantel in the upper third of FDA AER volume (#70 of 2,679).

Important: Adverse event reports do not establish that a drug caused or contributed to the event. Consult your veterinarian before making treatment decisions.
3,498
Total Reports
106
Deaths Reported
3.0%
Death-coded share of reports

Active Ingredients

Praziquantel

Administration Routes

OralUnknownSubcutaneousParenteralIntramuscularTopicalOtherOphthalmicSubconjunctivalIntraocular

Species Affected

Cat 1,512
Unknown 1,033
Dog 920
Human 28
Other 2
Cockatiel 1
Chinchilla 1
Chicken 1

Most Affected Breeds

Unknown 1,065
Domestic Shorthair 701
Cat (unknown) 472
Domestic Longhair 125
Dog (unknown) 97
Retriever - Labrador 73
Chihuahua 62
Domestic Mediumhair 60
Crossbred Canine/dog 59
Siamese 42

Most Reported Reactions

Lack of efficacy (endoparasite) - tapeworm 618
Product label issues 329
Vomiting 324
Underfilling, Bottles 256
Lethargy (see also Central nervous system depression in 'Neurological') 249
Tablets, Abnormal 208
Diarrhoea 200
Emesis 195
Patient instructions for use on label confusing 188
Behavioural disorder NOS 170
Product Defect, General 155
UNPALATABLE 148

Outcome Breakdown

Outcome Unknown
1,401 (57.6%)
Recovered/Normal
655 (26.9%)
Ongoing
264 (10.9%)
Died
82 (3.4%)
Euthanized
24 (1.0%)
Recovered with Sequela
6 (0.2%)

Praziquantel: low death-coded share in the FDA AER row

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.

High-volume nationwide drug peers

Two openFDA-derived peer sets for Praziquantel, both floored at ≥50 reports so the neighborhoods stay in the advertised mass.

What to do with this drug

A report does not prove a drug caused the reaction; consult a veterinarian before acting on this data.

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

openFDA Animal & Veterinary Adverse Events (FDA CVM) for Praziquantel (#70 of 2,679 by report volume); death-coded 3.0%. PlainBreed drug row · report volume stamp 3,498 · vintage 2025.

Informational only. FDA adverse-event reports are voluntary and do not prove causation; consult a veterinarian before acting on them. Verify with FDA CVM →