Thrombocytosis after Ilunocitinib (Zenrelia) in dogs

33 reports to the FDA describe thrombocytosis in dogs given Ilunocitinib. That is 1.5% of all reports for this medicine, compared with 0.2% across reports for all dog medicines, so it is reported unusually often with this medicine.

33Reports

30%Marked serious

0.0%Recovered

15%Died or euthanised

150 daysTypical onset

How soon it started

Same day

0 0.0%

1–2 days

3 13%

3–7 days

0 0.0%

1–4 weeks

0 0.0%

Over a month

20 87%

How the animals did

Still unwell when reported

13 39%

Euthanised

5 15%

Not known

15 45%

Problems reported at the same time

Decreased haematocrit

13 39%

Liver problems

11 33%

Decreased haemoglobin

11 33%

Decreased red blood cell count

11 33%

10 30%

8 24%

8 24%

8 24%

Age of the animals

Under 1 year

1–3 years

4–7 years

8–11 years

12+ years

About this medicine

Ilunocitinib controls itching from allergies (tablet, a JAK inhibitor).

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

Questions owners ask

Can Ilunocitinib cause thrombocytosis in dogs?: 33 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 150 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).

Thrombocytosis with similar medicines

Thrombocytosis after Oclacitinib (Apoquel) 119 reports · 0.4% of its reports
Thrombocytosis after Cyclosporine (Atopica) 78 reports · 0.5% of its reports

All reported side effects of Ilunocitinib in dogs · Medicines most reported with thrombocytosis