Erythema multiforme
Acute target-lesion eruption triggered mostly by herpes simplex and Mycoplasma. Typical raised targets in an acral spread, EM minor versus major, telling it apart from SJS, urticaria and MIRM, symptomatic care, and valaciclovir suppression for recurrent disease.
Tier 2Condition
Written with AI assistance and fact-checked against the sources below. For exam study, not clinical decisions. How notes are made
At a glance
- An acute, self-limiting immune reaction of skin and mucosa, mostly to infection, not drugs. HSV causes most adult cases, Mycoplasma pneumoniae more in children and young adults.
- Hallmark: raised typical targets with three zones, in an acral distribution (backs of hands, palms, forearms, feet), spreading towards the trunk.
- EM minor has no or mild mucosal disease. EM major adds significant mucosal involvement, usually the mouth. Both have under 10% skin detachment.
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Sources
- Therapeutic Guidelines: DermatologyAU/NZTherapeutic Guidelines Limited, eTG complete
- Kechichian E, Dupin N, Wetter DA, Ortonne N, Agbo-Godeau S, Chosidow O. Erythema multiforme. EClinicalMedicine 2024;77:102909EClinicalMedicine (The Lancet Discovery Science), 2024
- Soares A, Sokumbi O. Recent updates in the treatment of erythema multiforme. Medicina (Kaunas) 2021;57(9):921Medicina (MDPI), 2021
- Canavan TN, Mathes EF, Frieden I, Shinkai K. Mycoplasma pneumoniae-induced rash and mucositis as a syndrome distinct from Stevens-Johnson syndrome and erythema multiforme: a systematic review. J Am Acad Dermatol 2015;72:239-245Journal of the American Academy of Dermatology, 2015
- Trayes KP, Love G, Studdiford JS. Erythema multiforme: recognition and management. Am Fam Physician 2019;100(2):82-88American Family Physician, 2019
- Last updated
- 14 November 2026
What changed
- 14 November 2026 Personal emails, About story and Australian-style copy