Ear infection after Metronidazole in dogs

The FDA has received 33 reports of ear infection in dogs after Metronidazole. That is 1.1% 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.

33Reports

67%Marked serious

9.1%Recovered

3.0%Died or euthanised

31 daysTypical onset

How soon it started

Same day

3 12%

1–2 days

2 8.0%

3–7 days

3 12%

1–4 weeks

4 16%

Over a month

13 52%

How the animals did

Recovered

3 9.1%

Still unwell when reported

15 45%

Died

1 3.0%

Not known

14 42%

Problems reported at the same time

17 52%

16 48%

14 42%

14 42%

9 27%

Didn't work as expected

6 18%

Loose stool

6 18%

Dehydration

5 15%

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 ear infection in dogs?: 33 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 31 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).

Ear infection with similar medicines

Ear infection after Amoxicillin + Clavulanate (Clavamox) 33 reports · 0.6% of its reports
Ear infection after Doxycycline 21 reports · 0.5% of its reports
Ear infection after Enrofloxacin (Baytril) 27 reports · 0.7% of its reports

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