Moxidectin (ProHeart 6) side effects in dogs
50,598 reports sent to the FDA between 1997 and 2026 involve Moxidectin in dogs. The most reported problems were vomiting, allergic reaction, swelling. 54% were marked serious, and where it was recorded, signs eased after stopping the medicine in 7% of cases.
About this medicine
Moxidectin prevents heartworm disease (monthly topical, or a 6- or 12-month injection for dogs).
Products with this ingredient include ProHeart 6, ProHeart 12. The FDA hides brand names in its public data, so these reports cover every product with the same active ingredients.
Some herding breeds (for example Collies) carry the MDR1 gene variant and can be more sensitive to this drug class at high doses.
Most reported side effects
Share = percentage of this medicine's reports that mention the problem. One report can list several problems.
Reports that it didn't work
Some reports are about the medicine not working (for example a dog still getting fleas or heartworm), not about a side effect.
How soon problems started
Time from the first dose to the first sign, where both dates were reported (31,223 reports).
How the animals did
Breeds named most often
Popular breeds appear more often because there are more of them.
- Labrador Retriever 4,779 reports
- Bull - American Pit Terrier 1,958 reports
- German Shepherd Dog 1,618 reports
- Boxer (german Boxer) 1,434 reports
- Chihuahua 1,401 reports
- Golden Retriever 1,317 reports
- Yorkshire Terrier 1,129 reports
- Shih Tzu 1,004 reports
- Beagle 951 reports
- Dachshund 924 reports