Drug profile

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

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

22
adverse-event reports
4.5%
death-coded share
Cat
most-reported species
11
Lack of efficacy (ectoparasite) - flea - 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.
22
Total Reports
1
Deaths Reported
4.5%
Death Rate

Active Ingredients

Fipronil And (S)-Methoprene

Administration Routes

TopicalUnknown

Species Affected

Cat 13
Dog 9

Most Affected Breeds

Cat (unknown) 5
Domestic Shorthair 4
Persian 3
Shepherd Dog - German 2
Deutsche Dogge, Great Dane 1
Sheepdog - Shetland 1
Dachshund (unspecified) 1
Maine Coon 1
Chihuahua 1
Pug 1

Most Reported Reactions

Lack of efficacy (ectoparasite) - flea 11
Panting 3
Pruritus 2
Emesis 1
Conjunctivitis 1
Alopecia NOS 1
Erythema (for urticaria see Immune SOC) 1
Self trauma 1
Application site alopecia 1
Low tear flow 1
Other abnormal test result NOS 1
Drooling 1

Outcome Breakdown

Outcome Unknown
16 (72.7%)
Recovered/Normal
5 (22.7%)
Euthanized
1 (4.5%)

Fipronil And (S)-Methoprene Adverse Event Insights

22 reports name Fipronil And (S)-Methoprene; 1 recorded a death outcome (4.5% of reported events, not a population-level mortality rate). Active ingredient: Fipronil And (S)-Methoprene. Administration routes: Topical, Unknown.

By species: Cat (13 reports), Dog (9 reports). By breed: Cat (unknown) (5), Domestic Shorthair (4), Persian (3).

Leading clinical signs: Lack of efficacy (ectoparasite) - flea (11), Panting (3), Pruritus (2), Emesis (1). Outcome, 22 coded reports: Outcome Unknown leads at 72.7%.

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.