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Erythema Nodosum

By

The Manual's Editorial Staff

Medically Reviewed Jan 2021 | Modified Sep 2022
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What is erythema nodosum?

Erythema nodosum is an inflammatory reaction in the layer of fat under your skin. It causes red or purplish bumps under your skin, often on your shins.

  • Erythema nodosum is most common in people in their 20s and 30s, especially women

  • It's usually caused by a reaction to a medicine or an infection

  • In addition to the bumps on your skin, you may have fever and joint pain

  • It usually gets better on its own in 3 to 6 weeks

What causes erythema nodosum?

Common causes include:

Less common causes:

What are the symptoms of erythema nodosum?

Symptoms include:

  • Painful, red or purple bumps, usually on your shins

  • Fever

  • Joint pain

How can doctors tell if I have erythema nodosum?

Doctors can usually tell you have erythema nodosum by looking at the bumps on your skin. Sometimes to know for sure they'll do a biopsy (take out a small piece of tissue to look at under a microscope).

To find out what's causing your erythema nodosum, they may do other tests, such as:

How do doctors treat erythema nodosum?

Erythema nodosum gets better on its own after 3 to 6 weeks. If your erythema nodosum is caused by an infection, doctors will treat the infection. The following may help you lessen pain:

  • Bed rest

  • Cool compresses

  • Keeping your leg elevated

  • Taking nonsteroidal anti-inflammatory drugs (NSAIDs—such as aspirin or ibuprofen)

  • Sometimes, your doctor may have you take potassium iodide to help with symptoms

  • Sometimes, corticosteroids (medicines to lower swelling)

Drugs Mentioned In This Article

Generic Name Select Brand Names
Anacin Adult Low Strength, Aspergum, Aspir-Low, Aspirtab , Aspir-Trin , Bayer Advanced Aspirin, Bayer Aspirin, Bayer Aspirin Extra Strength, Bayer Aspirin Plus, Bayer Aspirin Regimen, Bayer Children's Aspirin, Bayer Extra Strength, Bayer Extra Strength Plus, Bayer Genuine Aspirin, Bayer Low Dose Aspirin Regimen, Bayer Womens Aspirin , BeneHealth Aspirin, Bufferin, Bufferin Extra Strength, Bufferin Low Dose, DURLAZA, Easprin , Ecotrin, Ecotrin Low Strength, Genacote, Halfprin, MiniPrin, St. Joseph Adult Low Strength, St. Joseph Aspirin, VAZALORE, Zero Order Release Aspirin, ZORprin
Advil, Advil Children's, Advil Children's Fever, Advil Infants', Advil Junior Strength, Advil Migraine, Caldolor, Children's Ibuprofen, ElixSure IB, Genpril , Ibren , IBU, Midol, Midol Cramps and Body Aches, Motrin, Motrin Children's, Motrin IB, Motrin Infants', Motrin Junior Strength, Motrin Migraine Pain, PediaCare Children's Pain Reliever/Fever Reducer IB, PediaCare Infants' Pain Reliever/Fever Reducer IB, Samson-8
Pima, SSKI
NOTE: This is the Consumer Version. DOCTORS: VIEW PROFESSIONAL VERSION
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