IL4 and asthma: However, dupilumab, a monoclonal antibody that works by blocking the receptor of IL-4 and IL-13 (IL-4R1) and is used for treating asthma and atopic dermatitis, has been reported to be associated with side effects such as plaque PsO, generalized pustular PsO and nail PsO, speculatively an effect of increased production of IL-23 and consequently IL-17, due to blockade of the regulatory pathway of IL-4 [33].