Drug profile

The FDA adverse-event record for Milbemycin Oxime, Lufenuron

6,743 adverse-event reports submitted to the FDA Center for Veterinary Medicine reference Milbemycin Oxime, Lufenuron. See the species affected, top reactions, and outcomes below.

6,743
adverse-event reports
0.9%
death-coded share
Dog
most-reported species
1,493
INEFFECTIVE, HEARTWORM LARVAE - top reaction
Verify with FDA CVM →
Important: Adverse event reports do not establish that a drug caused or contributed to the event. Consult your veterinarian before making treatment decisions.
6,743
Total Reports
63
Deaths Reported
0.9%
Death Rate

Active Ingredients

Milbemycin Oxime, Lufenuron

Administration Routes

OralUnknownTopicalIntrauterine

Species Affected

Dog 6,527
Unknown 196
Cat 10
Human 9
Goat 1

Most Affected Breeds

Crossbred Canine/dog 942
Retriever - Labrador 903
Dog (unknown) 355
Shepherd Dog - German 329
Retriever - Golden 322
Beagle 209
Unknown 206
Terrier - Yorkshire 150
Chihuahua 142
Boxer (German Boxer) 134

Most Reported Reactions

INEFFECTIVE, HEARTWORM LARVAE 1,493
Lack of efficacy (endoparasite) - hookworm 1,406
Vomiting 1,011
INEFFECTIVE, ASCARIDS NOS 838
Diarrhoea 583
Lethargy (see also Central nervous system depression in 'Neurological') 428
Lack of efficacy (endoparasite) - whipworm 424
Lack of efficacy - NOS 348
Lack of efficacy (ectoparasite) - flea 300
INEFFECTIVE, HOOKS 220
Underdose 184
Overdose 181

Outcome Breakdown

Outcome Unknown
4,561 (69.6%)
Recovered/Normal
1,798 (27.4%)
Ongoing
100 (1.5%)
Died
32 (0.5%)
Euthanized
31 (0.5%)
Recovered with Sequela
29 (0.4%)

Milbemycin Oxime, Lufenuron Adverse Event Insights

6,743 reports name Milbemycin Oxime, Lufenuron; 63 recorded a death outcome (0.9% of reported events, not a population-level mortality rate). Active ingredient: Milbemycin Oxime, Lufenuron. Administration routes: Oral, Unknown, Topical, Intrauterine.

By species: Dog (6,527 reports), Unknown (196 reports), Cat (10 reports). By breed: Crossbred Canine/dog (942), Retriever - Labrador (903), Dog (unknown) (355).

Leading clinical signs: INEFFECTIVE, HEARTWORM LARVAE (1,493), Lack of efficacy (endoparasite) - hookworm (1,406), Vomiting (1,011), INEFFECTIVE, ASCARIDS NOS (838). Outcome, 6,551 coded reports: Outcome Unknown leads at 69.6%.

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.