Hair loss after Metronidazole in dogs

The FDA has received 44 reports of hair loss in dogs after Metronidazole. That is 1.4% of all reports for this medicine, compared with 1.0% across reports for all dog medicines.

44Reports

59%Marked serious

16%Recovered

18%Died or euthanised

20 daysTypical onset

How soon it started

Same day

7 18%

1–2 days

3 7.9%

3–7 days

4 11%

1–4 weeks

7 18%

Over a month

17 45%

How the animals did

Recovered

7 16%

Still unwell when reported

17 39%

Died

1 2.3%

Euthanised

7 16%

Not known

12 27%

Problems reported at the same time

21 48%

20 45%

16 36%

15 34%

13 30%

12 27%

11 25%

10 23%

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 hair loss in dogs?: 44 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 20 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).

Hair loss with similar medicines

Hair loss after Amoxicillin + Clavulanate (Clavamox) 102 reports · 1.9% of its reports
Hair loss after Doxycycline 54 reports · 1.3% of its reports
Hair loss after Cefovecin (Convenia) 93 reports · 2.5% of its reports
Hair loss after Enrofloxacin (Baytril) 72 reports · 1.9% of its reports
Hair loss after Amoxicillin 26 reports · 1.9% of its reports

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