Drug profile

The FDA adverse-event record for Fipronil + (S)-Methoprene + Pyriproxyfen

40 adverse-event reports submitted to the FDA Center for Veterinary Medicine reference Fipronil + (S)-Methoprene + Pyriproxyfen. See the species affected, top reactions, and outcomes below.

40
adverse-event reports
0.0%
death-coded share
Dog
most-reported species
8
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.
40
Total Reports
0
Deaths Reported
0.0%
Death Rate

Active Ingredients

Fipronil + (S)-Methoprene + Pyriproxyfen

Administration Routes

TopicalUnknownOther

Species Affected

Dog 33
Cat 7

Most Affected Breeds

Crossbred Canine/dog 5
Domestic Shorthair 3
Retriever - Labrador 3
Shepherd Dog - German 3
Terrier - Yorkshire 3
Domestic Longhair 2
Shepherd Dog - Australian 2
Retriever - Golden 2
Persian 2
Beagle 2

Most Reported Reactions

Lack of efficacy (endoparasite) - heartworm 8
Other abnormal test result NOS 8
Vomiting 7
Lethargy (see also Central nervous system depression in 'Neurological') 6
Enlarged liver 4
Elevated serum alkaline phosphatase (SAP) 3
Licking 3
Agitation 3
INEFFECTIVE, HOOKS 3
Shaking 3
Weakness 3
Lack of efficacy (ectoparasite) - flea 2

Outcome Breakdown

Outcome Unknown
22 (55.0%)
Recovered/Normal
9 (22.5%)
Ongoing
9 (22.5%)

Fipronil + (S)-Methoprene + Pyriproxyfen Adverse Event Insights

40 reports name Fipronil + (S)-Methoprene + Pyriproxyfen; 0 recorded a death outcome (0.0% of reported events, not a population-level mortality rate). Active ingredient: Fipronil + (S)-Methoprene + Pyriproxyfen. Administration routes: Topical, Unknown, Other.

By species: Dog (33 reports), Cat (7 reports). By breed: Crossbred Canine/dog (5), Domestic Shorthair (3), Retriever - Labrador (3).

Leading clinical signs: Lack of efficacy (endoparasite) - heartworm (8), Other abnormal test result NOS (8), Vomiting (7), Lethargy (see also Central nervous system depression in 'Neurological') (6). Outcome, 40 coded reports: Outcome Unknown leads at 55.0%.

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.