Didn't stop worms after Moxidectin (ProHeart 6) in dogs

9,537 reports to the FDA describe didn't stop worms in dogs given Moxidectin. That is 19% of all reports for this medicine, compared with 8.4% across reports for all dog medicines, so it is reported unusually often with this medicine.

9,537Reports

75%Marked serious

1.9%Recovered

0.1%Died or euthanised

178 daysTypical onset

How soon it started

Same day

151 2.3%

1–2 days

64 1.0%

3–7 days

78 1.2%

1–4 weeks

413 6.2%

Over a month

5,980 89%

How the animals did

Recovered

180 1.9%

Recovered with lasting effects

1 0.0%

Still unwell when reported

8,882 93%

Died

6 0.1%

Euthanised

1 0.0%

Not known

467 4.9%

Problems reported at the same time

Medication error

841 8.8%

Intentional misuse

505 5.3%

Didn't work as expected

241 2.5%

Drug dose administration interval too long

171 1.8%

Drug dose administration interval too short

113 1.2%

Overdose

81 0.8%

Didn't prevent heartworm

78 0.8%

Underdose

61 0.6%

Age of the animals

Under 1 year

400

1–3 years

3,536

4–7 years

2,899

8–11 years

1,786

12+ years

621

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.

Questions owners ask

Can Moxidectin cause didn't stop worms in dogs?: 9,537 reports link the two, but a report alone does not prove the medicine was the cause: other illnesses, other medicines or coincidence can be involved. Your vet can judge it for your animal.
How soon after a dose was it reported?: In half of the reports with dates, it started within 178 days of the first dose.
What should I do?: Don't give another dose until you've spoken to your vet, and keep the packaging so you can tell them the product and dose. Your vet can also report it to the FDA (or you can, through the manufacturer or FDA form 1932a).

Didn't stop worms with similar medicines

Didn't stop worms after Ivermectin + Pyrantel (Heartgard Plus) 32,467 reports · 22% of its reports
Didn't stop worms after Milbemycin Oxime + Spinosad (Trifexis) 4,483 reports · 3.5% of its reports
Didn't stop worms after Milbemycin Oxime + Praziquantel (Interceptor Plus) 6,097 reports · 19% of its reports
Didn't stop worms after Milbemycin Oxime (Interceptor) 4,308 reports · 14% of its reports
Didn't stop worms after Selamectin (Revolution) 2,317 reports · 7.9% of its reports
Didn't stop worms after Ivermectin (Heartgard) 254 reports · 2.1% of its reports
Didn't stop worms after Ivermectin + Praziquantel + Pyrantel (Iverhart Max) 1,299 reports · 15% of its reports
Didn't stop worms after Moxidectin + Pyrantel + Sarolaner (Simparica Trio) 132 reports · 11% of its reports

All reported side effects of Moxidectin in dogs · Medicines most reported with didn't stop worms