Drug profile

The FDA adverse-event record for Milbemycin/Lufenuron/Pzq Chew

4,022 adverse-event reports submitted to the FDA Center for Veterinary Medicine reference Milbemycin/Lufenuron/Pzq Chew. See the species affected, top reactions, and outcomes below.

4,022
adverse-event reports
1.6%
death-coded share
Dog
most-reported species
1,316
Lack of efficacy (endoparasite) - heartworm - 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.
4,022
Total Reports
64
Deaths Reported
1.6%
Death Rate

Active Ingredients

Milbemycin/Lufenuron/Pzq Chew

Administration Routes

OralUnknownDentalOculonasal

Species Affected

Dog 3,934
Unknown 88

Most Affected Breeds

Crossbred Canine/dog 1,084
Retriever - Labrador 430
Shepherd Dog - German 191
Retriever - Golden 186
Dog (unknown) 128
Pit Bull 110
Shepherd Dog - Australian 97
Beagle 93
Unknown 89
Chihuahua 78

Most Reported Reactions

Lack of efficacy (endoparasite) - heartworm 1,316
Lack of efficacy (endoparasite) - hookworm 630
Vomiting 448
Lack of efficacy (endoparasite) - roundworm NOS 340
Lack of efficacy (ectoparasite) - flea 214
Emesis (multiple) 208
Lack of efficacy (endoparasite) - tapeworm 162
Diarrhoea 155
Drug dose omission 131
Lack of efficacy (endoparasite) - whipworm 121
Lethargy (see also Central nervous system depression in Neurological) 101
Seizure NOS 90

Outcome Breakdown

Ongoing
2,854 (72.5%)
Recovered/Normal
867 (22.0%)
Outcome Unknown
121 (3.1%)
Died
32 (0.8%)
Euthanized
32 (0.8%)
Recovered with Sequela
29 (0.7%)

Milbemycin/Lufenuron/Pzq Chew Adverse Event Insights

4,022 reports name Milbemycin/Lufenuron/Pzq Chew; 64 recorded a death outcome (1.6% of reported events, not a population-level mortality rate). Active ingredient: Milbemycin/Lufenuron/Pzq Chew. Administration routes: Oral, Unknown, Dental, Oculonasal.

By species: Dog (3,934 reports), Unknown (88 reports). By breed: Crossbred Canine/dog (1,084), Retriever - Labrador (430), Shepherd Dog - German (191).

Leading clinical signs: Lack of efficacy (endoparasite) - heartworm (1,316), Lack of efficacy (endoparasite) - hookworm (630), Vomiting (448), Lack of efficacy (endoparasite) - roundworm NOS (340). Outcome, 3,935 coded reports: Ongoing leads at 72.5%.

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.