Dupilumab and alopecia: A Janus effect.

Atopic dermatitis (AD) and alopecia areata (AA) are two common skin diseases that can coexist in the same patient, sharing some pathogenetic mechanisms such as the overexpression of interleukin 4 (IL4) and interleukin 13 (IL13). Recently, cases of AA healing during treatment with anti-IL4/IL13 monoclonal antibody dupilumab (D) for AD were reported. However, cases of appearance of AA have been described during D treatment too. We report two patients that experienced these two opposite effects of D.