Weight loss after Imidacloprid + Moxidectin (Advantage Multi) in cats

188 reports to the FDA describe weight loss in cats given Imidacloprid + Moxidectin. That is 2.3% of all reports for this medicine, compared with 4.6% across reports for all cat medicines, so it is reported less often than average with this medicine.

188Reports
81%Marked serious
23%Recovered
16%Died or euthanised
4 daysTypical onset
SponsoredWorried about your pet? Ask a veterinarian online, 24/7

How soon it started

Same day
31 25%
1–2 days
24 20%
3–7 days
19 15%
1–4 weeks
30 24%
Over a month
19 15%

How the animals did

Recovered
44 23%
Still unwell when reported
12 6.4%
Died
17 9.0%
Euthanised
14 7.4%
Not known
101 54%

Problems reported at the same time

Age of the animals

Under 1 year
13
1–3 years
27
4–7 years
33
8–11 years
45
12+ years
62

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 weight loss in cats?
188 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 4 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).

Weight loss with similar medicines

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