Drug profile

The FDA adverse-event record for Ivermectin/Pyrantel Pamoate

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

135
adverse-event reports
3.0%
death-coded share
Dog
most-reported species
49
INEFFECTIVE, HEARTWORM LARVAE - 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.
135
Total Reports
4
Deaths Reported
3.0%
Death Rate

Active Ingredients

Ivermectin/Pyrantel Pamoate

Administration Routes

OralUnknown

Species Affected

Dog 135

Most Affected Breeds

Retriever - Labrador 23
Crossbred Canine/dog 13
Shepherd Dog - German 9
Retriever - Golden 8
Beagle 7
Shepherd Dog - Australian 6
Boxer (German Boxer) 5
Greyhound 5
Terrier (unspecified) 4
Rottweiler 4

Most Reported Reactions

INEFFECTIVE, HEARTWORM LARVAE 49
Lack of efficacy (endoparasite) - heartworm 13
Diarrhoea 12
INEFFECTIVE, HOOKS 12
Lack of efficacy - NOS 10
Vomiting 9
Lethargy (see also Central nervous system depression in 'Neurological') 8
Lack of efficacy (endoparasite) - hookworm 7
Anorexia 6
Underdose 5
Emesis 5
Emesis (multiple) 5

Outcome Breakdown

Outcome Unknown
53 (39.3%)
Ongoing
42 (31.1%)
Recovered/Normal
36 (26.7%)
Euthanized
3 (2.2%)
Died
1 (0.7%)

Ivermectin/Pyrantel Pamoate Adverse Event Insights

135 reports name Ivermectin/Pyrantel Pamoate; 4 recorded a death outcome (3.0% of reported events, not a population-level mortality rate). Active ingredient: Ivermectin/Pyrantel Pamoate. Administration routes: Oral, Unknown.

By species: Dog (135 reports). By breed: Retriever - Labrador (23), Crossbred Canine/dog (13), Shepherd Dog - German (9).

Leading clinical signs: INEFFECTIVE, HEARTWORM LARVAE (49), Lack of efficacy (endoparasite) - heartworm (13), Diarrhoea (12), INEFFECTIVE, HOOKS (12). Outcome, 135 coded reports: Outcome Unknown leads at 39.3%.

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.