IL31 and contact dermatitis: In murine models of contact dermatitis, the administration of KOR agonists such as nalbuphine and nalfurafine not only suppressed scratching behavior but also exerted potent anti-inflammatory effects, characterized by the downregulation of the pruritogenic cytokine interleukin-31 (IL-31) and the upregulation of the anti-inflammatory cytokine IL-10 (Inan et al., 2019; Elliott et al., 2016).