Itching after Imidacloprid + Moxidectin (Advantage Multi) in cats

1,531 reports to the FDA describe itching in cats given Imidacloprid + Moxidectin. That is 19% of all reports for this medicine, compared with 8.9% across reports for all cat medicines, so it is reported unusually often with this medicine.

1,531Reports

59%Marked serious

29%Recovered

1.4%Died or euthanised

3 daysTypical onset

How soon it started

Same day

302 29%

1–2 days

216 21%

3–7 days

151 14%

1–4 weeks

289 28%

Over a month

89 8.5%

How the animals did

Recovered

437 29%

Still unwell when reported

54 3.5%

Died

10 0.7%

Euthanised

11 0.7%

Not known

1,019 67%

Problems reported at the same time

Hair loss

377 25%

Didn't stop fleas

303 20%

Application site reaction

262 17%

Behaviour change

180 12%

Restlessness or agitation

135 8.8%

Skin rash or irritation

134 8.8%

Lethargy

131 8.6%

Skin redness

130 8.5%

Age of the animals

Under 1 year

160

1–3 years

404

4–7 years

337

8–11 years

264

12+ years

189

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 itching in cats?: 1,531 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 3 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).

Itching with similar medicines

Itching after Spinosad (Comfortis) 439 reports · 3.8% of its reports
Itching after Nitenpyram (Capstar) 1,904 reports · 22% of its reports
Itching after Lufenuron 84 reports · 7.6% of its reports
Itching after Flumethrin + Imidacloprid (Seresto) 210 reports · 31% of its reports
Itching after Imidacloprid + Pyriproxyfen 222 reports · 34% of its reports
Itching after Fipronil 63 reports · 13% of its reports
Itching after Fipronil + S-methoprene (Frontline Plus) 68 reports · 19% of its reports
Itching after Imidacloprid 42 reports · 17% of its reports

All reported side effects of Imidacloprid + Moxidectin in cats · Medicines most reported with itching