Lethargy after Imidacloprid + Moxidectin (Advantage Multi) in dogs

2,000 reports to the FDA describe lethargy in dogs given Imidacloprid + Moxidectin. That is 15% of all reports for this medicine, compared with 11% across reports for all dog medicines.

2,000Reports

59%Marked serious

42%Recovered

5.1%Died or euthanised

Same dayTypical onset

How soon it started

Same day

693 51%

1–2 days

357 26%

3–7 days

97 7.1%

1–4 weeks

116 8.5%

Over a month

102 7.5%

How the animals did

Recovered

824 41%

Recovered with lasting effects

10 0.5%

Still unwell when reported

92 4.6%

Died

55 2.8%

Euthanised

47 2.4%

Not known

972 49%

Problems reported at the same time

651 33%

605 30%

291 15%

273 14%

223 11%

198 9.9%

171 8.6%

Restlessness or agitation

146 7.3%

Age of the animals

Under 1 year

386

1–3 years

650

4–7 years

491

8–11 years

298

12+ years

116

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 lethargy in dogs?: 2,000 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 the same day 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).

Lethargy with similar medicines

Lethargy after Spinosad (Comfortis) 7,303 reports · 13% of its reports
Lethargy after Lufenuron + Milbemycin Oxime (Sentinel) 2,341 reports · 9.0% of its reports
Lethargy after Nitenpyram (Capstar) 1,204 reports · 11% of its reports
Lethargy after Lufenuron + Milbemycin Oxime + Praziquantel (Sentinel Spectrum) 666 reports · 6.7% of its reports
Lethargy after Fipronil + S-methoprene (Frontline Plus) 447 reports · 15% of its reports
Lethargy after Flumethrin + Imidacloprid (Seresto) 250 reports · 11% of its reports
Lethargy after Imidacloprid 196 reports · 10% of its reports
Lethargy after Fipronil 185 reports · 13% of its reports
Lethargy after Lufenuron 205 reports · 20% of its reports
Lethargy after Imidacloprid + Permethrin + Pyriproxyfen 106 reports · 14% of its reports

All reported side effects of Imidacloprid + Moxidectin in dogs · Medicines most reported with lethargy