Drug profile

The FDA adverse-event record for Milbemycin Oxime, Praziquantel

1,195 adverse-event reports submitted to the FDA Center for Veterinary Medicine reference Milbemycin Oxime, Praziquantel. See the species affected, top reactions, and outcomes below.

1,195
adverse-event reports
3.7%
death-coded share
Dog
most-reported species
314
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.
1,195
Total Reports
44
Deaths Reported
3.7%
Death Rate

Active Ingredients

Milbemycin Oxime, Praziquantel

Administration Routes

OralUnknownTopicalOther

Species Affected

Dog 1,178
Unknown 15
Human 1
Cat 1

Most Affected Breeds

Retriever - Labrador 164
Crossbred Canine/dog 83
Retriever - Golden 67
Shepherd Dog - German 65
Dog (unknown) 54
Shepherd Dog - Australian 45
Beagle 37
Chihuahua 36
Pit Bull 34
Terrier - Yorkshire 26

Most Reported Reactions

Lack of efficacy (endoparasite) - heartworm 314
Vomiting 203
Diarrhoea 88
Lack of efficacy (endoparasite) - hookworm 88
Lethargy (see also Central nervous system depression in Neurological) 87
Lack of efficacy (endoparasite) - tapeworm 63
Other abnormal test result NOS 54
Lack of efficacy (endoparasite) - NOS 50
Seizure NOS 47
Lack of efficacy (endoparasite) - roundworm NOS 47
Not eating 43
Loose stool 39

Outcome Breakdown

Outcome Unknown
631 (53.5%)
Recovered/Normal
258 (21.9%)
Ongoing
244 (20.7%)
Died
24 (2.0%)
Euthanized
20 (1.7%)
Recovered with Sequela
3 (0.3%)

Milbemycin Oxime, Praziquantel Adverse Event Insights

1,195 reports name Milbemycin Oxime, Praziquantel; 44 recorded a death outcome (3.7% of reported events, not a population-level mortality rate). Active ingredient: Milbemycin Oxime, Praziquantel. Administration routes: Oral, Unknown, Topical, Other.

By species: Dog (1,178 reports), Unknown (15 reports), Human (1 reports). By breed: Retriever - Labrador (164), Crossbred Canine/dog (83), Retriever - Golden (67).

Leading clinical signs: Lack of efficacy (endoparasite) - heartworm (314), Vomiting (203), Diarrhoea (88), Lack of efficacy (endoparasite) - hookworm (88). Outcome, 1,180 coded reports: Outcome Unknown leads at 53.5%.

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.