Abnormal ultrasound finding after Fenbendazole in dogs

25 reports to the FDA describe abnormal ultrasound finding in dogs given Fenbendazole. That is 0.4% of all reports for this medicine, compared with 0.5% across reports for all dog medicines.

25Reports

76%Marked serious

8.0%Recovered

40%Died or euthanised

27 daysTypical onset

How soon it started

Same day

2 10%

1–2 days

1 5.0%

3–7 days

5 25%

1–4 weeks

6 30%

Over a month

6 30%

How the animals did

Recovered

1 4.0%

Recovered with lasting effects

1 4.0%

Still unwell when reported

10 40%

Died

3 12%

Euthanised

7 28%

Not known

3 12%

Problems reported at the same time

15 60%

14 56%

14 56%

13 52%

12 48%

10 40%

10 40%

Abnormal radiograph finding

9 36%

Age of the animals

Under 1 year

1–3 years

4–7 years

8–11 years

12+ years

About this medicine

Fenbendazole treats intestinal worms and some other parasites.

Questions owners ask

Can Fenbendazole cause abnormal ultrasound finding in dogs?: 25 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 27 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).

Abnormal ultrasound finding with similar medicines

Abnormal ultrasound finding after Pyrantel + Sarolaner (Simparica Trio) 58 reports · 0.1% of its reports

All reported side effects of Fenbendazole in dogs · Medicines most reported with abnormal ultrasound finding