Oclacitinib (brand name Apoquel) is a veterinary medication used in the control of atopic dermatitis and pruritus from allergic dermatitis in dogs at least 12 months of age. Chemically, it is a synthetic cyclohexylamino pyrrolopyrimidine janus kinase inhibitor that is relatively selective for JAK1. It inhibits signal transduction when the JAK is activated and thus helps downregulate expression of inflammatory cytokines. While oclacitinib is effective, its long-term safety is currently unknown. Oclacitinib was approved by the FDA in 2013.