Erythema Multiforme By Julia Benedetti, MD, Harvard Medical School Reviewed / Revised Apr 2022 | Modified Sep 2022 View Patient Education Etiology Symptoms and Signs Diagnosis Treatment Key Points Topic Resources Erythema Multiforme (Palm) Erythema Multiforme (Back) Erythema Multiforme (Abdomen) Erythema multiforme is an inflammatory reaction, characterized by target or iris skin lesions.