Leucocytosis after Feline Leukemia Vaccine in cats

26 reports to the FDA describe leucocytosis in cats given Feline Leukemia Vaccine. That is 3.3% of all reports for this medicine, compared with 0.9% across reports for all cat medicines, so it is reported unusually often with this medicine.

26Reports

73%Marked serious

31%Recovered

23%Died or euthanised

2 daysTypical onset

How soon it started

Same day

8 36%

1–2 days

7 32%

3–7 days

3 14%

1–4 weeks

2 9.1%

Over a month

2 9.1%

How the animals did

Recovered

8 31%

Still unwell when reported

9 35%

Euthanised

6 23%

Not known

3 12%

Problems reported at the same time

17 65%

17 65%

11 42%

9 35%

9 35%

8 31%

8 31%

8 31%

Age of the animals

Under 1 year

1–3 years

4–7 years

8–11 years

12+ years

About this medicine

Type: vaccine.

Mild, short-lived lethargy, soreness or a small lump at the injection site are the most commonly reported vaccine reactions.

Questions owners ask

Can Feline Leukemia Vaccine cause leucocytosis 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 2 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).

Leucocytosis with similar medicines

Leucocytosis after Rabies Vaccine 55 reports · 2.1% of its reports
Leucocytosis after Feline Core Vaccine 46 reports · 3.0% of its reports

All reported side effects of Feline Leukemia Vaccine in cats · Medicines most reported with leucocytosis