IL4 and Pruritus: Some animal experiments investigated the antipruritic effect of Qingpeng ointment by using the histamine-induced itch mice model, and the results showed that Qingpeng ointment could significantly decrease thymic stromal lymphopoietin (TSLP) mRNA and IL-4 mRNA levels in the skin and increase the pruritus threshold of histamine phosphate [50, 51].