OPRM1 and Pruritus: In a DNFB-induced contact dermatitis model of male Swiss Webster mice, the KOR agonist, but DOR and MOR partial agonist (Figure 1), Nalbuphine (10 mg/kg; s.c.; 20 min prior to DNFB), was found to attenuate pruritus, as well as to decrease IL-31 and to increase IL-10 levels in the skin of the animals.