Reaction profile

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

76 FDA adverse-event reports reference lack of efficacy (endoparasite nos) (VeDDRA 2436). See the species, breeds, and drugs most associated with it below.

76
reports citing this reaction
19.7%
death-coded share
Dog
most-affected species
Milbemycin Oxime + Praziquantel
most-associated drug
Verify with FDA CVM →
76
Total Reports
15
Deaths
19.7%
Death Rate

Species Most Affected

Dog 51
Cattle 19
Horse 5
Chicken 1

Breeds Most Affected

Cattle (other) 15
Dog (unknown) 7
Retriever - Golden 6
Retriever - Labrador 4
Terrier - Yorkshire 4
Quarter Horse 3
Chihuahua 3
Pit Bull 2
Aberdeen Angus 2
Siberian Husky 2

Associated Drugs

Milbemycin Oxime + Praziquantel 42
Fenbendazol Suspension 16
Bovine Virus*5/Past M+Mh Lv/Lb 9
Clos P*2/Cl Oth*4/H.Somnus Kb 9
Milbemycin Oxime + Spinosad 8
Clostr Perf*2/Clos Others*4 Kb 6
Trenbolone Acet/Estradiol Impl 6
Tildipirosin Injectable 5
Trenbolone Acet/Estrad Sr Imp 4
Ibr / Pi3 (Orig S-P Us) Lv 4
Praziquantel;Moxidectin 4
Ibr/Brsv/P13/Bvd T1, T2(Us) Lv 4
Moxidectin 3
Sarolaner 3
Lotilaner 3
Pyrantel Pamoate;Sarolaner 3
Past Mult / M Haem Cattle Lb 2
Florfenicol/Flunixin Inj-Triac 2
Dinotefuran + Pyriproxyfen 2
Praziquantel; Moxidectin 1

Lack of efficacy (endoparasite NOS) Reaction Insights

76 reports name Lack of efficacy (endoparasite NOS); 15 recorded a death outcome (19.7% of reported events, not a population-level mortality rate). VeDDRA code: 2436.

By species: Dog (51 reports), Cattle (19 reports), Horse (5 reports). By breed: Cattle (other) (15), Dog (unknown) (7), Retriever - Golden (6).

Most co-reported drugs: Milbemycin Oxime + Praziquantel (42 reports), Fenbendazol Suspension (16 reports), Bovine Virus*5/Past M+Mh Lv/Lb (9 reports), Clos P*2/Cl Oth*4/H.Somnus Kb (9 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.