2025 Volume 87 Issue 7 Pages 723-726
A four-year-old Toy Poodle treated with oclacitinib for one year presented with transient myoglobinuria associated with elevated serum creatine kinase (CK) levels only after exercise. An association between myoglobinuria and oclacitinib was suspected. An exercise stress test with or without oclacitinib was repeated twice on different days. Myoglobinuria and increased serum CK levels occurred only after testing with oclacitinib. The dog was diagnosed with exercise-induced mild rhabdomyolysis, which was presumably provoked by oclacitinib based on the results of the exercise stress tests. Rhabdomyolysis was considered an idiosyncratic adverse event for oclacitinib. This is the first report of exercise-induced mild rhabdomyolysis associated with oclacitinib in a dog.