Liver problems after Ilunocitinib (Zenrelia) in dogs

The FDA has received 263 reports of liver problems in dogs after Ilunocitinib. That is 12% of all reports for this medicine, compared with 4.6% across reports for all dog medicines, so it is reported unusually often with this medicine.

263Reports

43%Marked serious

8.4%Recovered

19%Died or euthanised

93 daysTypical onset

How soon it started

Same day

8 3.8%

1–2 days

12 5.8%

3–7 days

11 5.3%

1–4 weeks

30 14%

Over a month

147 71%

How the animals did

Recovered

22 8.4%

Still unwell when reported

81 31%

Died

13 4.9%

Euthanised

37 14%

Not known

110 42%

Problems reported at the same time

75 29%

70 27%

70 27%

48 18%

48 18%

47 18%

44 17%

Decreased haematocrit

44 17%

Age of the animals

Under 1 year

1–3 years

4–7 years

8–11 years

101

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 liver problems in dogs?: 263 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 93 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).

Liver problems with similar medicines

Liver problems after Oclacitinib (Apoquel) 2,601 reports · 9.0% of its reports
Liver problems after Cyclosporine (Atopica) 1,186 reports · 7.8% of its reports

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