Didn't work as expected after Flumethrin + Imidacloprid (Seresto) in dogs

209 reports to the FDA describe didn't work as expected in dogs given Flumethrin + Imidacloprid. That is 9.2% of all reports for this medicine, compared with 13% across reports for all dog medicines.

209Reports

18%Marked serious

1.0%Recovered

1.9%Died or euthanised

123 daysTypical onset

How soon it started

Same day

5 5.1%

1–2 days

5 5.1%

3–7 days

5 5.1%

1–4 weeks

12 12%

Over a month

71 72%

How the animals did

Recovered

1 0.5%

Recovered with lasting effects

1 0.5%

Still unwell when reported

53 25%

Died

3 1.4%

Euthanised

1 0.5%

Not known

150 72%

Problems reported at the same time

42 20%

19 9.1%

19 9.1%

16 7.7%

13 6.2%

12 5.7%

9 4.3%

8 3.8%

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 didn't work as expected in dogs?: 209 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 123 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).

Didn't work as expected with similar medicines

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Didn't work as expected after Lufenuron + Milbemycin Oxime (Sentinel) 4,480 reports · 17% of its reports
Didn't work as expected after Imidacloprid + Moxidectin (Advantage Multi) 631 reports · 4.8% of its reports
Didn't work as expected after Nitenpyram (Capstar) 803 reports · 7.4% of its reports
Didn't work as expected after Lufenuron + Milbemycin Oxime + Praziquantel (Sentinel Spectrum) 1,429 reports · 14% of its reports
Didn't work as expected after Fipronil + S-methoprene (Frontline Plus) 243 reports · 8.2% of its reports
Didn't work as expected after Imidacloprid 105 reports · 5.5% of its reports
Didn't work as expected after Fipronil 152 reports · 11% of its reports
Didn't work as expected after Imidacloprid + Permethrin + Pyriproxyfen 30 reports · 4.1% of its reports
Didn't work as expected after Imidacloprid + Permethrin 70 reports · 15% of its reports

All reported side effects of Flumethrin + Imidacloprid in dogs · Medicines most reported with didn't work as expected