Drug profile

The FDA adverse-event record for Ivermectin, Pyrantel Pamoate

219 adverse-event reports submitted to the FDA Center for Veterinary Medicine reference Ivermectin, Pyrantel Pamoate. See the species affected, top reactions, and outcomes below.

219
adverse-event reports
5.5%
death-coded share
Dog
most-reported species
70
Lack of efficacy (endoparasite) - heartworm - top reaction
Verify with FDA CVM →
Important: Adverse event reports do not establish that a drug caused or contributed to the event. Consult your veterinarian before making treatment decisions.
219
Total Reports
12
Deaths Reported
5.5%
Death Rate

Active Ingredients

Ivermectin, Pyrantel Pamoate

Administration Routes

OralUnknown

Species Affected

Dog 217
Unknown 2

Most Affected Breeds

Retriever - Labrador 41
Shepherd Dog - German 12
Crossbred Canine/dog 11
Dog (unknown) 11
Boxer (German Boxer) 9
Terrier - Bull - American Pit 8
Terrier (unspecified) 7
Shih Tzu 6
Chihuahua 5
Beagle 5

Most Reported Reactions

Lack of efficacy (endoparasite) - heartworm 70
INEFFECTIVE, HEARTWORM LARVAE 51
Lack of efficacy - NOS 35
Lethargy (see also Central nervous system depression in 'Neurological') 21
Vomiting 19
Diarrhoea 17
Seizure NOS 11
Ataxia 8
Death 7
Anorexia 5
Death by euthanasia 5
Panting 5

Outcome Breakdown

Ongoing
136 (62.7%)
Outcome Unknown
40 (18.4%)
Recovered/Normal
29 (13.4%)
Died
7 (3.2%)
Euthanized
5 (2.3%)

Ivermectin, Pyrantel Pamoate Adverse Event Insights

219 reports name Ivermectin, Pyrantel Pamoate; 12 recorded a death outcome (5.5% of reported events, not a population-level mortality rate). Active ingredient: Ivermectin, Pyrantel Pamoate. Administration routes: Oral, Unknown.

By species: Dog (217 reports), Unknown (2 reports). By breed: Retriever - Labrador (41), Shepherd Dog - German (12), Crossbred Canine/dog (11).

Leading clinical signs: Lack of efficacy (endoparasite) - heartworm (70), INEFFECTIVE, HEARTWORM LARVAE (51), Lack of efficacy - NOS (35), Lethargy (see also Central nervous system depression in 'Neurological') (21). Outcome, 217 coded reports: Ongoing leads at 62.7%.

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.