OSM and Pruritus: Recent data implicate Th2‐associated cytokines such as interleukin‐4 (IL‐4), IL‐13, IL‐31 and oncostatin M (OSM) as important mediators of pruritus and responsible for PN typical epidermal hyperplasia, inflammation and fibrosis.2, 5, 6, 7, 8, 9