Severe Toxicosis Secondary to Accidental Oclacitinib Ingestion in Three Cats

OBJECTIVE: To describe the clinical course, outcome, necropsy findings, possible mechanisms of toxicosis, and treatment implications for three cats with acute kidney injury and associated systemic signs secondary to accidental oclacitinib ingestion. SERIES SUMMARY: Three cats ingested large (>100 mg/kg) overdoses of oclacitinib, leading to severe acute kidney injury and associated systemic illness. Two of the three cats subsequently died or were euthanized, while the third cat made a full recovery after receiving intensive supportive care. Necropsies were performed on the two deceased cats, with no definitive mechanism for toxicosis identified. NEW OR UNIQUE INFORMATION PROVIDED: This is the first case series of accidental oclacitinib toxicosis in cats. Recognition of this emerging concern can aid clinicians in minimizing exposure risks where possible, as well as providing prompt treatment in overdose situations.