Leucopenia after Amoxicillin + Clavulanate (Clavamox) in cats

The FDA has received 26 reports of leucopenia in cats after Amoxicillin + Clavulanate. That is 1.1% of all reports for this medicine, compared with 0.4% across reports for all cat medicines, so it is reported unusually often with this medicine.

26Reports

35%Marked serious

12%Recovered

50%Died or euthanised

8 daysTypical onset

How soon it started

Same day

2 17%

1–2 days

2 17%

3–7 days

1 8.3%

1–4 weeks

5 42%

Over a month

2 17%

How the animals did

Recovered

3 12%

Still unwell when reported

3 12%

Died

9 35%

Euthanised

4 15%

Not known

7 27%

Problems reported at the same time

16 62%

12 46%

12 46%

10 38%

Neutropenia

9 35%

Liver problems

9 35%

Vomiting

8 31%

Fever

8 31%

Age of the animals

Under 1 year

1–3 years

4–7 years

8–11 years

12+ years

About this medicine

Amoxicillin treats bacterial infections.

Products with this combination include Clavamox. The FDA hides brand names in its public data, so these reports cover every product with the same active ingredients.

Questions owners ask

Can Amoxicillin + Clavulanate cause leucopenia in cats?: 26 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 8 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).

Leucopenia with similar medicines

Leucopenia after Cefovecin (Convenia) 125 reports · 1.4% of its reports
Leucopenia after Enrofloxacin (Baytril) 26 reports · 1.6% of its reports

All reported side effects of Amoxicillin + Clavulanate in cats · Medicines most reported with leucopenia