Erythema multiforme
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.
Causes
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.
Allergic reaction
Allergic reactions are sensitivities to substances called allergens that come into contact with the skin, nose, eyes, respiratory tract, and gastroin...
Infections that may lead to EM include:
- Viruses, such as herpes simplex that cause cold sores and genital herpes (most common)
Herpes simplex
Oral herpes is an infection of the lips, mouth, or gums due to the herpes simplex virus. It causes small, painful blisters commonly called cold sore...
ImageRead Article Now Book Mark Article - Bacteria, such as Mycoplasma pneumoniaethat cause lung infection
Mycoplasma pneumoniae
Pneumonia is inflamed or swollen lung tissue due to infection with a germ. Mycoplasma pneumonia is caused by the bacteria Mycoplasma pneumoniae (M pn...
ImageRead Article Now Book Mark Article - Fungi, such as Histoplasma capsulatum, that cause histoplasmosis
Histoplasmosis
Histoplasmosis is an infection that occurs from breathing in the spores of the fungus Histoplasma capsulatum.
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Medicines that may cause EM include:
- NSAIDs
- Allopurinol (treats gout)
- Certain antibiotics, such as sulfonamides and aminopenicillins
- Anti-seizure medicines
Systemic illnesses that are associated with EM include:
- Inflammatory bowel disease, such as Crohn disease
Crohn disease
Crohn disease is a disease where parts of the digestive tract become inflamed. It most often involves the lower end of the small intestine and the be...
ImageRead Article Now Book Mark Article - Systemic lupus erythematosus
Systemic lupus erythematosus
Systemic lupus erythematosus (SLE) is an autoimmune disease. In this disease, the immune system of the body mistakenly attacks healthy tissue. It c...
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EM occurs mostly in adults 20 to 40 years old. People with EM may have family members who have had EM as well.
Symptoms
Symptoms of EM include:
- Low-grade fever
Fever
Fever is the temporary increase in the body's temperature in response to a disease or illness. A child has a fever when the temperature is at or abov...
ImageRead Article Now Book Mark Article - Headache
- Sore throat
- Cough
- Runny nose
- General ill feeling
General ill feeling
Malaise is a general feeling of discomfort, illness, or lack of well-being.
Read Article Now Book Mark Article - Itchy skin
Itchy
Itching is a tingling or irritation of the skin that makes you want to scratch the area. Itching may occur all over the body or only in one location...
ImageRead Article Now Book Mark Article - Joint aches
- Many skin lesions (sores or abnormal areas)
Skin lesions
Rashes involve changes in the color, feeling or texture of your skin.
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Skin sores may:
- Start quickly
- Come back
- Spread
- Be raised or discolored
- Look like hives
- Have a central sore surrounded by pale red rings, also called a target, iris, or bulls-eye
- Have liquid-filled bumps or blisters of various sizes
- Be located on the upper body, legs, arms, palms, hands, or feet
- Include the face or lips
- Appear evenly on both sides of the body (symmetrical)
Other symptoms may include:
- Bloodshot eyes
Bloodshot eyes
Eye redness is most often due to swollen or dilated blood vessels. This makes the surface of the eye look red or bloodshot.
ImageRead Article Now Book Mark Article - Dry eyes
- Eye burning, itching, and discharge
Eye burning, itching, and discharge
Eye burning with discharge is burning, itching, or drainage from the eye of any substance other than tears.
ImageRead Article Now Book Mark Article - Eye pain
Eye pain
Pain in the eye may be described as a burning, throbbing, aching, or stabbing sensation in or around the eye. It may also feel like you have a forei...
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Mouth sores
There are different types of mouth sores. They can occur anywhere in the mouth including bottom of the mouth, inner cheeks, gums, lips, and tongue....
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There are two forms of EM:
- EM minor usually involves the skin and sometimes mouth sores.
- EM major often starts with a fever and joint aches. Besides the skin sores and mouth sores, there may be sores in the eyes, genitals, lung airways, or gut.
Exams and Tests
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:
- Skin lesion biopsy
Skin lesion biopsy
A skin lesion biopsy is when a small amount of skin is removed so it can be examined under a microscope. The skin is tested to look for skin conditi...
ImageRead Article Now Book Mark Article - Examination of skin tissue under a microscope
Treatment
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:
- Medicines, such as antihistamines, to control itching
- Moist compresses applied to the skin
- Pain medicines to reduce fever and discomfort
- Mouthwashes to ease discomfort of mouth sores that interferes with eating and drinking
- Antibiotics for skin infections
- Corticosteroids to control inflammation
- Medicines for eye symptoms
Good hygiene may help prevent secondary infections (infections that occur from treating the first infection).
Secondary infections
A secondary infection is an infection that occurs during or after treatment for another infection. It may be caused by the first treatment or by cha...
Use of sunscreen, protective clothing, and avoiding excessive exposure to sun may prevent the recurrence of EM.
Outlook (Prognosis)
Mild forms of EM usually get better in 2 to 6 weeks, but the problem may return.
Possible Complications
Complications of EM may include:
- Patchy skin color
- Return of EM, especially with HSV infection
When to Contact a Medical Professional
Contact your provider right away if you have symptoms of EM.
Reviewed By
Elika Hoss, MD, Assistant Professor of Dermatology, Mayo Clinic, Scottsdale, AZ. Also reviewed by David C. Dugdale, MD, Medical Director, Brenda Conaway, Editorial Director, and the A.D.A.M. Editorial team.
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Holland KE. Acquired rashes in the older child. In: Kleigman RM, Toth H, Bordini BJ, Basel D, eds. Nelson Pediatric Symptom-Based Diagnosis. 2nd ed. Philadelphia, PA: Elsevier; 2023:chap 61.
Lalor L, Shah KN. Urticaria and erythema multiforme. In: Long SS, ed. Principles and Practice of Pediatric Infectious Diseases. 6th ed. Philadelphia, PA: Elsevier; 2023:chap 71.
Rubenstein JB, Spektor T. Conjunctivitis: infectious and noninfectious. In: Yanoff M, Duker JS, eds. Ophthalmology. 5th ed. Philadelphia, PA: Elsevier; 2019:chap 4.6.
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