Dupilumab, a monoclonal antibody against interleukin-4 (IL-4) and interleukin-13 (IL-13) used for the treatment of atopic dermatitis, has been linked to hypersensitivity reactions resulting in facial redness, and there is growing evidence that dupilumab may increase susceptibility to yeast infections as well. The gene discussed is IL13; the disease is atopic eczema.