Decreased haemoglobin after Ilunocitinib (Zenrelia) in dogs

The FDA has received 96 reports of decreased haemoglobin in dogs after Ilunocitinib. That is 4.4% of all reports for this medicine, compared with 0.1% across reports for all dog medicines, so it is reported unusually often with this medicine.

96Reports

38%Marked serious

10%Recovered

11%Died or euthanised

126 daysTypical onset

How soon it started

Same day

1 1.3%

1–2 days

0 0.0%

3–7 days

3 3.8%

1–4 weeks

17 22%

Over a month

58 73%

How the animals did

Recovered

10 10%

Still unwell when reported

34 35%

Died

1 1.0%

Euthanised

10 10%

Not known

41 43%

Problems reported at the same time

Decreased haematocrit

72 75%

Decreased red blood cell count

71 74%

39 41%

35 36%

35 36%

33 34%

32 33%

Decreased percentage of reticulocytes

29 30%

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 decreased haemoglobin in dogs?: 96 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 126 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).

Decreased haemoglobin with similar medicines

Decreased haemoglobin after Oclacitinib (Apoquel) 93 reports · 0.3% of its reports

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