Ixekizumab and herpes zoster in an erythrodermic patient.

Ixekizumab is an injectable monoclonal antibody against IL-17A approved by the US Food and Drug Administration for the treatment of plaque psoriasis, psoriatic arthritis, and ankylosing spondylitis. We present what we believe is the first case of herpes zoster (shingles) in a patient 12 weeks after starting ixekizumab for presumed erythrodermic psoriasis. It is important to be aware of potential side effects of immunomodulatory medications, particularly those that are new to the market.