Reaction profile

The FDA adverse-event record for lack of efficacy (ectoparasite) - tick nos

15,484 FDA adverse-event reports reference lack of efficacy (ectoparasite) - tick nos (VeDDRA 2658). See the species, breeds, and drugs most associated with it below.

15,484
reports citing this reaction
0.9%
death-coded share
Dog
most-affected species
Afoxolaner
most-associated drug
Verify with FDA CVM →
15,484
Total Reports
141
Deaths
0.9%
Death Rate

Species Most Affected

Dog 14,827
Cat 617
Cattle 31
Unknown 3
Other Canids 2
Other 2
Marsupial 1
Deer 1

Breeds Most Affected

Retriever - Labrador 1,741
Dog (unknown) 1,388
Crossbred Canine/dog 1,301
Retriever - Golden 1,208
Shepherd Dog - German 752
Shepherd Dog - Australian 499
Beagle 360
Terrier - Yorkshire 338
Domestic Shorthair 337
Shih Tzu 321

Associated Drugs

Afoxolaner 4,524
Fluralaner 13.64% 12-Week Chew 2,804
Pyrantel Pamoate;Sarolaner 2,765
Fluralaner Chew Tablets 1,566
Sarolaner 1,183
Recombinant E. Coli Bl21;Recombinant E. Coli Ecl19 862
Lotilaner 811
Recombitek Lyme - 2126.R0 701
Selamectin 476
Fluralaner Spot-On Solution 438
Milbemycin Oxime + Spinosad 250
Ivermectin + Pyrantel As Pamoate Salt 250
Milbemycin Oxime + Praziquantel 240
Recombinant E. Coli Bl21;Recombinant E. Coli Ecl19 152
Fluralaner 13.64% Chew Tablets 138
Fluralaner 5.46% 1-Month Chew 126
Borrelia Burgdorferi Bacterin 123
Selamectin;Sarolaner 117
Imidacloprid, Flumethrin 92
Canine B Burgdorferi *2 Alu Kb 86

Lack of efficacy (ectoparasite) - tick NOS Reaction Insights

15,484 reports name Lack of efficacy (ectoparasite) - tick NOS; 141 recorded a death outcome (0.9% of reported events, not a population-level mortality rate). VeDDRA code: 2658.

By species: Dog (14,827 reports), Cat (617 reports), Cattle (31 reports). By breed: Retriever - Labrador (1,741), Dog (unknown) (1,388), Crossbred Canine/dog (1,301).

Most co-reported drugs: Afoxolaner (4,524 reports), Fluralaner 13.64% 12-Week Chew (2,804 reports), Pyrantel Pamoate;Sarolaner (2,765 reports), Fluralaner Chew Tablets (1,566 reports).

Read these counts as reporting volume, not risk: per our methodology, co-reporting reflects temporal association captured in voluntary submissions, not proof that a drug caused this reaction. A widely-prescribed drug will rack up more raw co-reports at an identical true rate than a rarely-used one, so compare within similar-exposure products.

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.