Didn't stop worms after Imidacloprid + Moxidectin (Advantage Multi) in dogs

821 reports to the FDA describe didn't stop worms in dogs given Imidacloprid + Moxidectin. That is 6.3% of all reports for this medicine, compared with 8.4% across reports for all dog medicines.

821Reports

48%Marked serious

15%Recovered

2.3%Died or euthanised

26 daysTypical onset

How soon it started

Same day

24 4.5%

1–2 days

16 3.0%

3–7 days

49 9.3%

1–4 weeks

215 41%

Over a month

225 43%

How the animals did

Recovered

127 15%

Still unwell when reported

40 4.9%

Died

10 1.2%

Euthanised

9 1.1%

Not known

635 77%

Problems reported at the same time

Diarrhea

222 27%

Didn't work as expected

84 10%

77 9.4%

46 5.6%

41 5.0%

38 4.6%

34 4.1%

21 2.6%

Age of the animals

Under 1 year

142

1–3 years

257

4–7 years

202

8–11 years

127

12+ years

About this medicine

Imidacloprid kills fleas (spot-on or collar). Moxidectin prevents heartworm disease (monthly topical, or a 6- or 12-month injection for dogs).

Products with this combination include Advantage Multi. The FDA hides brand names in its public data, so these reports cover every product with the same active ingredients.

Questions owners ask

Can Imidacloprid + Moxidectin cause didn't stop worms in dogs?: 821 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 26 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

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Didn't stop worms after Lufenuron + Milbemycin Oxime (Sentinel) 4,911 reports · 19% of its reports
Didn't stop worms after Nitenpyram (Capstar) 28 reports · 0.3% of its reports
Didn't stop worms after Lufenuron + Milbemycin Oxime + Praziquantel (Sentinel Spectrum) 2,556 reports · 26% of its reports
Didn't stop worms after Fipronil + S-methoprene (Frontline Plus) 57 reports · 1.9% of its reports
Didn't stop worms after Flumethrin + Imidacloprid (Seresto) 80 reports · 3.5% of its reports
Didn't stop worms after Fipronil 52 reports · 3.7% of its reports
Didn't stop worms after Imidacloprid + Permethrin + Pyriproxyfen 30 reports · 4.1% of its reports
Didn't stop worms after Imidacloprid + Permethrin 20 reports · 4.3% of its reports

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