Seizures after Imidacloprid + Moxidectin (Advantage Multi) in cats

156 reports to the FDA describe seizures in cats given Imidacloprid + Moxidectin. That is 1.9% of all reports for this medicine, compared with 2.6% across reports for all cat medicines.

156Reports
81%Marked serious
41%Recovered
24%Died or euthanised
Same dayTypical onset
SponsoredWorried about your pet? Ask a veterinarian online, 24/7

How soon it started

Same day
60 52%
1–2 days
38 33%
3–7 days
7 6.1%
1–4 weeks
6 5.2%
Over a month
4 3.5%

How the animals did

Recovered
63 40%
Recovered with lasting effects
1 0.6%
Still unwell when reported
4 2.6%
Died
26 17%
Euthanised
12 7.7%
Not known
50 32%

Problems reported at the same time

Age of the animals

Under 1 year
38
1–3 years
35
4–7 years
32
8–11 years
21
12+ years
21

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 seizures in cats?
156 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).

Seizures with similar medicines

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