Lethargy after Lufenuron in dogs

The FDA has received 205 reports of lethargy in dogs after Lufenuron. That is 20% of all reports for this medicine, compared with 11% across reports for all dog medicines, so it is reported unusually often with this medicine.

205Reports

3.9%Marked serious

2.4%Recovered

12%Died or euthanised

82 daysTypical onset

How soon it started

Same day

1 10%

1–2 days

2 20%

3–7 days

0 0.0%

1–4 weeks

2 20%

Over a month

5 50%

How the animals did

Recovered

5 2.4%

Still unwell when reported

4 2.0%

Died

25 12%

Not known

171 83%

Problems reported at the same time

86 42%

79 39%

44 21%

28 14%

24 12%

23 11%

14 6.8%

13 6.3%

Age of the animals

Under 1 year

1–3 years

4–7 years

8–11 years

12+ years

About this medicine

Lufenuron stops flea eggs from developing.

Questions owners ask

Can Lufenuron cause lethargy in dogs?: 205 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 82 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).

Lethargy with similar medicines

Lethargy after Spinosad (Comfortis) 7,303 reports · 13% of its reports
Lethargy after Lufenuron + Milbemycin Oxime (Sentinel) 2,341 reports · 9.0% of its reports
Lethargy after Imidacloprid + Moxidectin (Advantage Multi) 2,000 reports · 15% of its reports
Lethargy after Nitenpyram (Capstar) 1,204 reports · 11% of its reports
Lethargy after Lufenuron + Milbemycin Oxime + Praziquantel (Sentinel Spectrum) 666 reports · 6.7% of its reports
Lethargy after Fipronil + S-methoprene (Frontline Plus) 447 reports · 15% of its reports
Lethargy after Flumethrin + Imidacloprid (Seresto) 250 reports · 11% of its reports
Lethargy after Imidacloprid 196 reports · 10% of its reports
Lethargy after Fipronil 185 reports · 13% of its reports
Lethargy after Imidacloprid + Permethrin + Pyriproxyfen 106 reports · 14% of its reports

All reported side effects of Lufenuron in dogs · Medicines most reported with lethargy