Excessive thirst after Flumethrin + Imidacloprid (Seresto) in dogs

The FDA has received 21 reports of excessive thirst in dogs after Flumethrin + Imidacloprid. That is 0.9% of all reports for this medicine, compared with 1.4% across reports for all dog medicines, so it is reported less often than average with this medicine.

21Reports

67%Marked serious

19%Recovered

9.5%Died or euthanised

70 daysTypical onset

How soon it started

Same day

1 7.7%

1–2 days

0 0.0%

3–7 days

1 7.7%

1–4 weeks

4 31%

Over a month

7 54%

How the animals did

Recovered

4 19%

Still unwell when reported

6 29%

Euthanised

2 9.5%

Not known

9 43%

Problems reported at the same time

Vomiting

10 48%

Excessive urination

9 43%

8 38%

7 33%

6 29%

5 24%

5 24%

5 24%

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 excessive thirst in dogs?: 21 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 70 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).

Excessive thirst with similar medicines

Excessive thirst after Spinosad (Comfortis) 374 reports · 0.7% of its reports
Excessive thirst after Lufenuron + Milbemycin Oxime (Sentinel) 131 reports · 0.5% of its reports
Excessive thirst after Imidacloprid + Moxidectin (Advantage Multi) 114 reports · 0.9% of its reports
Excessive thirst after Nitenpyram (Capstar) 50 reports · 0.5% of its reports
Excessive thirst after Fipronil + S-methoprene (Frontline Plus) 23 reports · 0.8% of its reports
Excessive thirst after Fipronil 23 reports · 1.6% of its reports

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