Dehydration after Metronidazole in cats

28 reports to the FDA describe dehydration in cats given Metronidazole. That is 7.1% of all reports for this medicine, compared with 2.0% across reports for all cat medicines, so it is reported unusually often with this medicine.

28Reports

93%Marked serious

36%Recovered

32%Died or euthanised

5 daysTypical onset

How soon it started

Same day

6 25%

1–2 days

4 17%

3–7 days

3 13%

1–4 weeks

6 25%

Over a month

5 21%

How the animals did

Recovered

10 36%

Still unwell when reported

7 25%

Died

4 14%

Euthanised

5 18%

Not known

2 7.1%

Problems reported at the same time

17 61%

14 50%

11 39%

11 39%

9 32%

8 29%

Didn't work as expected

8 29%

Blood problems

7 25%

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 dehydration in cats?: 28 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 5 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).

Dehydration with similar medicines

Dehydration after Cefovecin (Convenia) 436 reports · 5.0% of its reports
Dehydration after Amoxicillin + Clavulanate (Clavamox) 108 reports · 4.5% of its reports
Dehydration after Enrofloxacin (Baytril) 49 reports · 3.1% of its reports

All reported side effects of Metronidazole in cats · Medicines most reported with dehydration