Tremors after Flumethrin + Imidacloprid (Seresto) in dogs

The FDA has received 66 reports of tremors in dogs after Flumethrin + Imidacloprid. That is 2.9% of all reports for this medicine, compared with 3.4% across reports for all dog medicines.

66Reports

48%Marked serious

39%Recovered

3.0%Died or euthanised

9 daysTypical onset

How soon it started

Same day

7 14%

1–2 days

8 16%

3–7 days

7 14%

1–4 weeks

11 22%

Over a month

16 33%

How the animals did

Recovered

26 39%

Still unwell when reported

13 20%

Died

1 1.5%

Euthanised

1 1.5%

Not known

25 38%

Problems reported at the same time

21 32%

20 30%

19 29%

17 26%

16 24%

15 23%

15 23%

9 14%

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).

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

Questions owners ask

Can Flumethrin + Imidacloprid cause tremors in dogs?: 66 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 9 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).

Tremors with similar medicines

Tremors after Spinosad (Comfortis) 2,268 reports · 4.0% of its reports
Tremors after Lufenuron + Milbemycin Oxime (Sentinel) 590 reports · 2.3% of its reports
Tremors after Imidacloprid + Moxidectin (Advantage Multi) 837 reports · 6.4% of its reports
Tremors after Nitenpyram (Capstar) 402 reports · 3.7% of its reports
Tremors after Lufenuron + Milbemycin Oxime + Praziquantel (Sentinel Spectrum) 213 reports · 2.1% of its reports
Tremors after Fipronil + S-methoprene (Frontline Plus) 141 reports · 4.8% of its reports
Tremors after Imidacloprid 58 reports · 3.0% of its reports
Tremors after Fipronil 65 reports · 4.6% of its reports
Tremors after Lufenuron 33 reports · 3.2% of its reports
Tremors after Imidacloprid + Permethrin + Pyriproxyfen 35 reports · 4.7% of its reports

All reported side effects of Flumethrin + Imidacloprid in dogs · Medicines most reported with tremors