Breathing problems after Fipronil in cats

The FDA has received 59 reports of breathing problems in cats after Fipronil. That is 12% of all reports for this medicine, compared with 4.7% across reports for all cat medicines, so it is reported unusually often with this medicine.

59Reports
29%Marked serious
53%Recovered
3.4%Died or euthanised
10 daysTypical onset
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How soon it started

Same day
9 19%
1–2 days
6 13%
3–7 days
6 13%
1–4 weeks
20 42%
Over a month
7 15%

How the animals did

Recovered
31 53%
Still unwell when reported
15 25%
Died
1 1.7%
Euthanised
1 1.7%
Not known
11 19%

Problems reported at the same time

12 20%
Excessive licking and/or grooming
7 12%
Increased heart rate
7 12%
Dilated pupils
7 12%
Drooling
4 6.8%

Age of the animals

Under 1 year
5
1–3 years
16
4–7 years
21
8–11 years
8
12+ years
8

About this medicine

Fipronil kills fleas and ticks (spot-on).

Questions owners ask

Can Fipronil cause breathing problems in cats?
59 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 10 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).

Breathing problems with similar medicines

All reported side effects of Fipronil in cats · Medicines most reported with breathing problems