IL4 and acne: Up to now, most of the therapeutic approaches for these diseases have targeted inflammation: (1) dupilumab, a dual inhibitor of IL-4 and IL-13, was recently approved to treat AD [314]; (2) monoclonal antibodies inhibiting IL-12, IL-23, or IL-17 are being developed for the treatment of psoriasis [315]; (3) a topical drug, ivermectin, for the treatment of mild-to-moderate rosacea has an anti-inflammatory effect [316]; and (4) anti-inflammatory drugs are also used to treat acne vulgaris, although the first line treatment of acne vulgaris is antibiotics [317].