Kidney problems after Spinosad (Comfortis) in cats

The FDA has received 108 reports of kidney problems in cats after Spinosad. That is 0.9% of all reports for this medicine, compared with 4.5% across reports for all cat medicines, so it is reported less often than average with this medicine.

108Reports
86%Marked serious
24%Recovered
46%Died or euthanised
2 daysTypical onset
SponsoredWorried about your pet? Ask a veterinarian online, 24/7

How soon it started

Same day
30 36%
1–2 days
13 16%
3–7 days
10 12%
1–4 weeks
8 9.6%
Over a month
22 27%

How the animals did

Recovered
6 5.6%
Recovered with lasting effects
20 19%
Still unwell when reported
18 17%
Died
37 34%
Euthanised
13 12%
Not known
14 13%

Problems reported at the same time

Age of the animals

Under 1 year
0
1–3 years
13
4–7 years
17
8–11 years
21
12+ years
53

About this medicine

Spinosad kills fleas; monthly chewable.

Products with this ingredient include Comfortis. The FDA hides brand names in its public data, so these reports cover every product with the same active ingredients.

Questions owners ask

Can Spinosad cause kidney problems in cats?
108 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 2 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).

Kidney problems with similar medicines

All reported side effects of Spinosad in cats · Medicines most reported with kidney problems