Pronounced: AIR-uh-THEE-ma no-DOSE-um
by Ricker Polsdorfer, MD
Erythema nodosum is the name given to tender lumps on the legs and sometimes the arms. They are caused by inflammation of the fat or connective tissue beneath the skin.
Erythema nodosum is thought to be a type of autoimmune reaction. It may be caused by:
Sometimes the cause of erythema nodosum is not known.
Risk Factors TOP
This condition is rare. It is more common in females and young adults aged 20-30 years old.
Having any of the causes listed above will only slightly increase your risk of the disorder.
You will be asked about your symptoms and medical history. A physical exam will be done, which may diagnose the problem based on a visual exam. You may be referred to a doctor that focuses on skin problems or infectious diseases.
Your bodily fluids and cells may be tested to look for a cause. This can be done with:
Images may be taken of your bodily structures. This can be done with a chest x-ray and other imaging tests.
If a cause can be identified, it will be treated. For the nodules themselves, pain relief is all that is needed. They tend to resolve on their own in about 6 weeks. They will not cause scarring. Treatment options include the following:
Pain relief includes:
Other medications such as steroids, may be necessary in severe cases.
Some of the infectious causes can be avoided by practicing good hygiene, which includes:
American Academy of Dermatology
Family Doctor—American Academy of Family Physicians
Canadian Dermatology Association
Erythema nodosum. EBSCO DynaMed Plus website. Available at: http://www.dynamed.com/topics/dmp~AN~T116219/Erythema-nodosum Updated February 23, 2016. Accessed August 18, 2017.
Erythema nodosum. DermNet New Zealand website. Available at: https://www.dermnetnz.org/topics/erythema-nodosum. Accessed August 18, 2017.
Erythema nodosum. Better Health Channel website. Available at: https://www.betterhealth.vic.gov.au/health/conditionsandtreatments/erythema-nodosum. Updated April 2016. Accessed August 18, 2017.
Requena L, Yus ES. Erythema nodosum. Dermatol Clin. 2008;26(4):425-438.
Last reviewed August 2017 by EBSCO Medical Review Board Michael Woods, MD, FAAP
Last Updated: 8/7/2015
EBSCO Information Services is fully accredited by URAC. URAC is an independent, nonprofit health care accrediting organization dedicated to promoting health care quality through accreditation, certification and commendation.
This content is reviewed regularly and is updated when new and relevant evidence is made available. This information is neither intended nor implied to be a substitute for professional medical advice. Always seek the advice of your physician or other qualified health provider prior to starting any new treatment or with questions regarding a medical condition.
To send comments or feedback to our Editorial Team regarding the content please email us at email@example.com. Our Health Library Support team will respond to your email request within 2 business days.