Skin redness after Imidacloprid + Moxidectin (Advantage Multi) in cats

The FDA has received 429 reports of skin redness in cats after Imidacloprid + Moxidectin. That is 5.3% of all reports for this medicine, compared with 2.2% across reports for all cat medicines, so it is reported unusually often with this medicine.

429Reports

69%Marked serious

32%Recovered

1.6%Died or euthanised

1 daysTypical onset

How soon it started

Same day

82 26%

1–2 days

115 37%

3–7 days

61 19%

1–4 weeks

37 12%

Over a month

18 5.8%

How the animals did

Recovered

136 32%

Still unwell when reported

11 2.6%

Died

2 0.5%

Euthanised

5 1.2%

Not known

275 64%

Problems reported at the same time

Hair loss

316 74%

Application site reaction

236 55%

Itching

130 30%

Skin rash or irritation

50 12%

Lethargy

35 8.2%

Behaviour change

31 7.2%

Restlessness or agitation

25 5.8%

Loss of appetite

20 4.7%

Age of the animals

Under 1 year

1–3 years

127

4–7 years

124

8–11 years

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 skin redness in cats?: 429 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 1 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).

Skin redness with similar medicines

Skin redness after Spinosad (Comfortis) 33 reports · 0.3% of its reports
Skin redness after Nitenpyram (Capstar) 48 reports · 0.5% of its reports
Skin redness after Flumethrin + Imidacloprid (Seresto) 69 reports · 10% of its reports
Skin redness after Imidacloprid + Pyriproxyfen 26 reports · 4.0% of its reports

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