Drug profile

The FDA adverse-event record for Afoxolaner 28.3 Mg Chewable Tablets

2,161 FDA reports name Afoxolaner 28.3 Mg Chewable Tablets, a high-volume drug in the CVM extract. Species, reactions, and outcomes follow.

#104 of 2,679
by report volume (all drugs)
2,161
adverse-event reports
1.7%
death-coded share
Dog
most-reported species

Corpus placement

According to the FDA Center for Veterinary Medicine openFDA adverse-event extract, Afoxolaner 28.3 Mg Chewable Tablets ranks #104 of 2679 by total reports (2,161) and #1011 of 1130 by death-coded share (1.7%). National dual: Milbemycin Oxime + Spinosad is #1 of 2679 drugs by total adverse-event reports (149,624) at death-coded-share rank 965 of 1130 drugs with at least 50 reports (2.3%); separately, Atlantic Salmon Transgenic Whole (Opafp-Ghc2 Rdna Construct Inserted Into The A-Locus In The Eo-1A Lineage) is #1 highest death-coded share at 97.8% (report rank #821).

149,624
Milbemycin Oxime + Spinosad reports (#1)
97.8%
Atlantic Salmon Transgenic Whole (Opafp-Ghc2 Rdna Construct Inserted Into The A-Locus In The Eo-1A Lineage) death share (#1)
#104
This drug, reports of 2679
#1011
This drug, death share of 1130

Report volume reflects how common a breed or drug is and how often owners and vets file — not actual risk. Death-coded share ranks are limited to entries with enough reports to be meaningful. The two maps do not agree at #1.

Release-over-release change

What changed in the latest FDA data snapshot

PlainBreed reconstructed the prior snapshot from dated openFDA partitions through 2025 Q4, then compared it with the 2026-07-27 openFDA export. Afoxolaner 28.3 Mg Chewable Tablets has 2,161 reports now versus 2,161 in that prior snapshot: 0 the same number of (0.0%).

Report change
+0
Death-coded reports
+0
Death-coded share
−0.0 pts

This compares reported-event counts in two source snapshots. It does not establish a change in real-world risk, product safety, or disease incidence.

Subscribe to Afoxolaner 28.3 Mg Chewable Tablets changes

Signature read: 2,161 reports place Afoxolaner 28.3 Mg Chewable Tablets in the upper third of FDA AER volume (#104 of 2,679).

Important: Adverse event reports do not establish that a drug caused or contributed to the event. Consult your veterinarian before making treatment decisions.
2,161
Total Reports
37
Deaths Reported
1.7%
Death-coded share of reports

Active Ingredients

Afoxolaner 28.3 Mg Chewable Tablets

Administration Routes

OralUnknownOther

Species Affected

Dog 1,964
Unknown 193
Human 2
Other 1
Cat 1

Most Affected Breeds

Shih Tzu 304
Crossbred Canine/dog 215
Unknown 205
Dog (unknown) 132
Lhasa Apso 131
Poodle - Miniature 94
Poodle - Toy 81
Terrier - Yorkshire 79
Maltese 69
Mixed (Dog) 61

Most Reported Reactions

Lack of efficacy (tick) 468
Skin disorders NOS 457
Vomiting 452
Lack of efficacy (flea) 301
Diarrhoea 167
Lethargy (see also Central nervous system depression in 'Neurological') 151
Pruritus 119
Lack of efficacy (ectoparasite) - NOS 86
Emesis 85
Anorexia 70
Scratching 64
Overdose 56

Outcome Breakdown

Outcome Unknown
1,229 (62.4%)
Recovered/Normal
605 (30.7%)
Ongoing
93 (4.7%)
Died
32 (1.6%)
Recovered with Sequela
6 (0.3%)
Euthanized
5 (0.3%)

Afoxolaner 28.3 Mg Chewable Tablets: low death-coded share in the FDA AER row

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.

High-volume nationwide drug peers

Two openFDA-derived peer sets for Afoxolaner 28.3 Mg Chewable Tablets, both floored at ≥50 reports so the neighborhoods stay in the advertised mass.

What to do with this drug

  • Compare Afoxolaner 28.3 Mg Chewable Tablets's report volume and death-coded share against similar drugs nationwide. See similar drugs
  • Read how death-coded share differs from a mortality rate before drawing conclusions. Understanding adverse events
  • Browse the full drug directory to compare report counts across products. All drugs

A report does not prove a drug caused the reaction; consult a veterinarian before acting on this data.

Source: FDA Center for Veterinary Medicine openFDA Animal & Veterinary Adverse Events (CVM AER) · 2025

openFDA Animal & Veterinary Adverse Events (FDA CVM) for Afoxolaner 28.3 Mg Chewable Tablets (#104 of 2,679 by report volume); death-coded 1.7%. PlainBreed drug row · report volume stamp 2,161 · vintage 2025.

Informational only. FDA adverse-event reports are voluntary and do not prove causation; consult a veterinarian before acting on them. Verify with FDA CVM →