Application site reaction after Amitraz + Fipronil + S-methoprene in dogs

The FDA has received 73 reports of application site reaction in dogs after Amitraz + Fipronil + S-methoprene. That is 16% of all reports for this medicine, compared with 0.4% across reports for all dog medicines, so it is reported unusually often with this medicine.

73Reports

82%Marked serious

19%Recovered

4.1%Died or euthanised

61 daysTypical onset

How soon it started

Same day

3 6.1%

1–2 days

2 4.1%

3–7 days

1 2.0%

1–4 weeks

8 16%

Over a month

35 71%

How the animals did

Recovered

14 19%

Still unwell when reported

10 14%

Euthanised

3 4.1%

Not known

46 63%

Problems reported at the same time

Lethargy

30 41%

Hair loss

23 32%

Itching

17 23%

Skin redness

11 15%

Skin rash or irritation

8 11%

Pemphigus foliaceus

7 9.6%

Liver problems

6 8.2%

Neutrophilia

5 6.8%

Age of the animals

Under 1 year

1–3 years

4–7 years

8–11 years

12+ years

About this medicine

Fipronil kills fleas and ticks (spot-on).

Questions owners ask

Can Amitraz + Fipronil + S-methoprene cause application site reaction in dogs?: 73 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 61 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).

Application site reaction with similar medicines

Application site reaction after Imidacloprid + Moxidectin (Advantage Multi) 658 reports · 5.0% of its reports
Application site reaction after Fipronil + S-methoprene (Frontline Plus) 185 reports · 6.3% of its reports
Application site reaction after Flumethrin + Imidacloprid (Seresto) 123 reports · 5.4% of its reports
Application site reaction after Imidacloprid + Permethrin + Pyriproxyfen 40 reports · 5.4% of its reports
Application site reaction after Cyphenothrin + Fipronil + S-methoprene 83 reports · 13% of its reports
Application site reaction after Fipronil + Pyriproxyfen + S-methoprene 24 reports · 5.6% of its reports

All reported side effects of Amitraz + Fipronil + S-methoprene in dogs · Medicines most reported with application site reaction