Blood problems after Feline Core Vaccine in cats

The FDA has received 117 reports of blood problems in cats after Feline Core Vaccine. That is 7.5% of all reports for this medicine, compared with 1.9% across reports for all cat medicines, so it is reported unusually often with this medicine.

117Reports

76%Marked serious

21%Recovered

26%Died or euthanised

9 daysTypical onset

How soon it started

Same day

20 18%

1–2 days

17 15%

3–7 days

15 13%

1–4 weeks

51 45%

Over a month

11 9.6%

How the animals did

Recovered

24 21%

Still unwell when reported

55 47%

Died

11 9.4%

Euthanised

19 16%

Not known

8 6.8%

Problems reported at the same time

89 76%

85 73%

65 56%

29 25%

28 24%

26 22%

24 21%

19 16%

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 Core Vaccine cause blood problems in cats?: 117 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 9 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).

Blood problems with similar medicines

Blood problems after Rabies Vaccine 117 reports · 4.5% of its reports
Blood problems after Feline Leukemia Vaccine 48 reports · 6.0% of its reports

All reported side effects of Feline Core Vaccine in cats · Medicines most reported with blood problems