Erythema multiforme major (EMM) is a hypersensitivity reaction that was previously thought to be part of a clinical spectrum including Stevens-Johnson syndrome (SJS) and toxic epidermal necrolysis, but it is now considered a distinct clinical entity.1,2 EMM is usually caused by an allergic reaction to pathogens, particularly herpes simplex virus (HSV; 50% of cases) and Mycoplasma pneumoniae, or to medications.2,3 EMM is a targetoid rash involving <10% of body surface area and has some mucous membrane involvement.2,3 Patients have a polymorphous eruption of macules, papules, and target lesions that are distributed symmetrically, typically originating in the distal extremities before spreading toward the trunk.2,3 Treatment may include systemic corticosteroids, intravenous immunoglobulin, plasmapheresis, and cyclosporine.3 Oral acyclovir and antibiotics may be used in cases of HSV and M pneumoniae infections, respectively.2 Any triggering medications must be stopped.3

10 Dermatologic Emergencies You Should Know About

Dermatologic emergencies are rare but often progress quickly and lead to significant morbidity and mortality. Most dermatologic emergencies result from an allergic reaction or infection, but some primary skin diseases can also become life-threatening. Prompt diagnosis is essential to improve outcomes, but it can be challenging because these conditions have multiple etiologies and variable presentations,…

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