Erythema multiforme (EM) is an acute skin reaction that comes from an infection or another trigger. EM is a self-limiting disease. This means it usually resolves on its own without treatment.
EM; Erythema multiforme minor; Erythema multiforme major; Erythema multiforme minor - erythema multiforme von Hebra; Acute bullous disorder - erythema multiforme; Herpes simplex - erythema multiforme
EM is a type of allergic reaction. In most cases, it occurs in response to an infection. In rare cases, it is caused by certain medicines or body-wide (systemic) illness.
Infections that may lead to EM include:
Medicines that may cause EM include:
Systemic illnesses that are associated with EM include:
EM occurs mostly in adults 20 to 40 years old. People with EM may have family members who have had EM as well.
Symptoms of EM include:
Skin sores may:
Other symptoms may include:
There are two forms of EM:
Your health care provider will look at your skin to diagnose EM. You'll be asked about your medical history, such as recent infections or medicines you've taken.
Tests may include:
EM usually goes away on its own with or without treatment.
Your provider will have you stop taking any medicines that may be causing the problem. But, don't stop taking medicines on your own without talking to your provider first.
Treatment may include:
Good hygiene may help prevent secondary infections (infections that occur from treating the first infection).
Use of sunscreen, protective clothing, and avoiding excessive exposure to sun may prevent the recurrence of EM.
Mild forms of EM usually get better in 2 to 6 weeks, but the problem may return.
Complications of EM may include:
Call your provider right away if you have symptoms of EM.
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Reviewed By: Ramin Fathi, MD, FAAD, Director, Phoenix Surgical Dermatology Group, Phoenix, AZ. Also reviewed by David Zieve, MD, MHA, Medical Director, Brenda Conaway, Editorial Director, and the A.D.A.M. Editorial team.