Ilunocitinib, sold under the brand name Zenrelia, is a veterinary medication used for the treatment of pruritus (itching) in dogs. It is a non-selective janus kinase inhibitor.

Ilunocitinib was approved for medical use in the United States in September 2024, and in Canada in December 2024.

Ilunocitinib is indicated for the control of pruritus associated with allergic dermatitis and control of atopic dermatitis in dogs at least twelve months of age.

It is not safe to administer vaccines to dogs that are concurrently receiving ilunocitinib.

Ilunocitinib was approved for medical use in the United States in September 2024, and in Canada in December 2024.

In June 2025, the Committee for Veterinary Medicinal Products of the European Medicines Agency adopted a positive opinion, recommending the granting of a marketing authorization for the veterinary medicinal product Zenrelia, film-coated tablets, intended for dogs. The applicant for this veterinary medicinal product is Elanco GmbH.

Ilunocitinib is the international nonproprietary name.

Ilunocitinib is sold under the brand name Zenrelia.