Neutropenia after Metronidazole in dogs

The FDA has received 75 reports of neutropenia in dogs after Metronidazole. That is 2.4% of all reports for this medicine, compared with 0.2% across reports for all dog medicines, so it is reported unusually often with this medicine.

75Reports

77%Marked serious

15%Recovered

39%Died or euthanised

14 daysTypical onset

How soon it started

Same day

13 20%

1–2 days

6 9.4%

3–7 days

7 11%

1–4 weeks

9 14%

Over a month

29 45%

How the animals did

Recovered

11 15%

Still unwell when reported

25 33%

Died

8 11%

Euthanised

21 28%

Not known

10 13%

Problems reported at the same time

45 60%

44 59%

40 53%

37 49%

34 45%

33 44%

33 44%

31 41%

Age of the animals

Under 1 year

1–3 years

4–7 years

8–11 years

12+ years

About this medicine

Metronidazole treats some bacterial and parasitic gut infections.

Questions owners ask

Can Metronidazole cause neutropenia in dogs?: 75 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 14 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).

Neutropenia with similar medicines

Neutropenia after Amoxicillin + Clavulanate (Clavamox) 57 reports · 1.1% of its reports
Neutropenia after Doxycycline 40 reports · 1.0% of its reports
Neutropenia after Cefovecin (Convenia) 46 reports · 1.2% of its reports
Neutropenia after Enrofloxacin (Baytril) 72 reports · 1.9% of its reports

All reported side effects of Metronidazole in dogs · Medicines most reported with neutropenia