Drug profile

The FDA adverse-event record for Afoxolaner 2.27% Chewable Tablet (136 Mg)

237 adverse-event reports submitted to the FDA Center for Veterinary Medicine reference Afoxolaner 2.27% Chewable Tablet (136 Mg). See the species affected, top reactions, and outcomes below.

237
adverse-event reports
3.0%
death-coded share
Dog
most-reported species
56
Vomiting - 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.
237
Total Reports
7
Deaths Reported
3.0%
Death Rate

Active Ingredients

Afoxolaner 2.27% Chewable Tablet (136 Mg)

Administration Routes

OralUnknown

Species Affected

Dog 235
Unknown 1
Horse 1

Most Affected Breeds

Retriever - Labrador 57
Retriever - Golden 26
Shepherd Dog - German 23
Crossbred Canine/dog 21
Rottweiler 12
Pit Bull 10
Dog (unknown) 8
Unknown 7
Boxer (German Boxer) 6
Collie - Border 4

Most Reported Reactions

Vomiting 56
Skin disorders NOS 37
Pruritus 34
Diarrhoea 25
Lethargy (see also Central nervous system depression in 'Neurological') 24
Lack of efficacy (ectoparasite) - flea 21
Lack of efficacy (ectoparasite) - tick NOS 18
Scratching 16
Erythema (for urticaria see Immune SOC) 16
Restlessness 13
Anorexia 12
Itching 12

Outcome Breakdown

Outcome Unknown
112 (47.5%)
Recovered/Normal
99 (41.9%)
Ongoing
11 (4.7%)
Died
7 (3.0%)
Recovered with Sequela
7 (3.0%)

Afoxolaner 2.27% Chewable Tablet (136 Mg) Adverse Event Insights

237 reports name Afoxolaner 2.27% Chewable Tablet (136 Mg); 7 recorded a death outcome (3.0% of reported events, not a population-level mortality rate). Active ingredient: Afoxolaner 2.27% Chewable Tablet (136 Mg). Administration routes: Oral, Unknown.

By species: Dog (235 reports), Unknown (1 reports), Horse (1 reports). By breed: Retriever - Labrador (57), Retriever - Golden (26), Shepherd Dog - German (23).

Leading clinical signs: Vomiting (56), Skin disorders NOS (37), Pruritus (34), Diarrhoea (25). Outcome, 236 coded reports: Outcome Unknown leads at 47.5%.

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.