Breathing problems after Imidacloprid + Moxidectin (Advantage Multi) in cats

The FDA has received 144 reports of breathing problems in cats after Imidacloprid + Moxidectin. That is 1.8% of all reports for this medicine, compared with 4.7% across reports for all cat medicines, so it is reported less often than average with this medicine.

144Reports

63%Marked serious

28%Recovered

23%Died or euthanised

Same dayTypical onset

How soon it started

Same day

56 56%

1–2 days

29 29%

3–7 days

6 6.0%

1–4 weeks

5 5.0%

Over a month

4 4.0%

How the animals did

Recovered

41 28%

Still unwell when reported

8 5.6%

Died

26 18%

Euthanised

7 4.9%

Not known

62 43%

Problems reported at the same time

Lethargy

56 39%

Loss of appetite

38 26%

Death

33 23%

Restlessness or agitation

30 21%

29 20%

28 19%

24 17%

22 15%

Age of the animals

Under 1 year

1–3 years

4–7 years

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 breathing problems in cats?: 144 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).

Breathing problems with similar medicines

Breathing problems after Spinosad (Comfortis) 261 reports · 2.3% of its reports
Breathing problems after Nitenpyram (Capstar) 2,180 reports · 25% of its reports
Breathing problems after Lufenuron 44 reports · 4.0% of its reports
Breathing problems after Flumethrin + Imidacloprid (Seresto) 21 reports · 3.1% of its reports
Breathing problems after Fipronil 59 reports · 12% of its reports
Breathing problems after Fipronil + S-methoprene (Frontline Plus) 28 reports · 7.6% of its reports

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