Didn't work as expected after Metronidazole in dogs

The FDA has received 407 reports of didn't work as expected in dogs after Metronidazole. That is 13% of all reports for this medicine, compared with 13% across reports for all dog medicines.

407Reports

57%Marked serious

11%Recovered

22%Died or euthanised

18 daysTypical onset

How soon it started

Same day

55 18%

1–2 days

37 12%

3–7 days

25 8.2%

1–4 weeks

71 23%

Over a month

116 38%

How the animals did

Recovered

44 11%

Recovered with lasting effects

2 0.5%

Still unwell when reported

150 37%

Died

39 9.6%

Euthanised

52 13%

Not known

120 29%

Problems reported at the same time

136 33%

120 29%

116 29%

90 22%

89 22%

77 19%

45 11%

41 10%

Age of the animals

Under 1 year

104

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 didn't work as expected in dogs?: 407 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 18 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).

Didn't work as expected with similar medicines

Didn't work as expected after Amoxicillin + Clavulanate (Clavamox) 1,093 reports · 20% of its reports
Didn't work as expected after Doxycycline 428 reports · 11% of its reports
Didn't work as expected after Cefovecin (Convenia) 584 reports · 15% of its reports
Didn't work as expected after Enrofloxacin (Baytril) 368 reports · 9.8% of its reports
Didn't work as expected after Amoxicillin 145 reports · 11% of its reports
Didn't work as expected after Enrofloxacin + Silver Sulfadiazine 32 reports · 15% of its reports
Didn't work as expected after Enrofloxacin + Ketoconazole + Triamcinolone 20 reports · 21% of its reports

All reported side effects of Metronidazole in dogs · Medicines most reported with didn't work as expected