Healthdirect Free Australian health advice you can count on.

Medical problem? Call 1800 022 222. If you need urgent medical help, call triple zero immediately

healthdirect Australia is a free service where you can talk to a nurse or doctor who can help you know what to do.

beginning of content

Erythema nodosum

3-minute read

What is erythema nodosum?

Erythema nodosum, or EN, is a skin condition that shows as a lumpy red rash, usually on the lower legs. It is sometimes caused by an illness, but about half the time there is no reason for it.

While the rash can be painful, it is harmless in itself. It usually settles down without specific treatment over several weeks.

What are the symptoms of erythema nodosum?

Painful red lumps or nodules gradually appear on the skin over a period of up to 10 days. They usually appear on the legs, from the knees down. They can also appear on the thighs, arms or face. The lumps can be as small as a grape or as big as an orange. They gradually turn purple, like an old bruise, before fading away.

Other symptoms can include:

A lumpy red rash, usually on the lower legs is a common symptom of erythema nodosum.

What causes erythema nodosum?

Erythema nodosum happens when the layer of fat that everybody has under their skin becomes inflamed or irritated.

It can be triggered by:

It can also come on in people who have:

But in about half of all people who get it, doctors can’t identify the cause.

How is erythema nodosum diagnosed?

The rash is diagnosed by a doctor based on how the bumps look and feel. Sometimes a biopsy (sample) of the skin is taken to make sure the diagnosis is right. If your doctor suspects that there is some other illness causing the erythema nodosum, they might ask you to have other tests.

Your doctor might order:

How is erythema nodosum treated?

Your doctor will treat any illness that is causing erythema nodosum.

General treatment for erythema nodosum might include:

  • anti-inflammatory medicine (some people can't take these — check with your doctor if unsure)
  • support stockings or bandages
  • resting, especially if the legs are sore and swollen
  • raising the feet and legs
  • cold packs

Most people find their erythema nodosum clears up in 2 to 4 weeks, without any need for medicine.

If you think you might have erythema nodosum, it is best to seek advice from your doctor.

Learn more here about the development and quality assurance of healthdirect content.

Last reviewed: July 2020

Back To Top

Need more information?

These trusted information partners have more on this topic.

Top results

ACD A-Z of Skin - Erythema nodosum

Erythema nodosum is the most common type of panniculitis (inflammation of the fat layer in the skin) leading to red, raised nodules usually over the shins, ankles and knees.

Read more on Australasian College of Dermatologists website

Erythema nodosum - Better Health Channel

Read more on Better Health Channel website

ACD A-Z of Skin - Panniculitis

Panniculitis refers to a group of conditions characterised by inflammation of the fat layer below the skin (sub-cutaneous fat). It can be localised to a particular part of the body or involve larger areas.

Read more on Australasian College of Dermatologists website

Erythema toxicum: newborns and babies | Raising Children Network

Up to half of all full-term babies get erythema toxicum. It’s a common and harmless rash that goes away by itself. Read more about erythema toxicum.

Read more on website

ACD A-Z of Skin - Erythema annulare centrifugum

Erythema annulare centrifugum (EAC) refers to an annular (ring-shaped) erythematous (red) skin eruption that tends to spread outwards whilst clearing centrally.

Read more on Australasian College of Dermatologists website

ACD A-Z of Skin - Erythema multiforme

Erythema multiforme (EM) is an acute skin condition that may be recurrent in some cases. It occurs most commonly in association with the herpes simplex virus as an immune response to the infection. Young males are most commonly affected.

Read more on Australasian College of Dermatologists website

ACD A-Z of Skin - Erythema ab igne

Erythema ab igne (EAI) is a skin reaction characterised by a pattern of erythema (redness) resembling a net or hyperpigmentation (increased pigmentation)...

Read more on Australasian College of Dermatologists website

ACD A-Z of Skin - Erythema dyschromicum perstans and lichen planus pigmentosus

The terms lichen planus pigmentosus (LPP), erythema dyschromicum perstans (EDP) and idiopathic eruptive macular pigmentation (IEMP) are names given to

Read more on Australasian College of Dermatologists website

ACD A-Z of Skin - Erythema infectiosum

Erythema infectiosum is usually a harmless childhood viral infection characterised by a classic slapped-cheek appearance or a lacy patterned rash. The infection can be associated with fevers.

Read more on Australasian College of Dermatologists website

ACD A-Z of Skin - Thalidomide

A-Z OF SKIN Thalidomide BACK TO A-Z SEARCH What is thalidomide? Thalidomide is notoriously well-known for its severe birth defects and associated temporary market withdrawal in 1961

Read more on Australasian College of Dermatologists website

Healthdirect 24hr 7 days a week hotline

24 hour health advice you can count on

1800 022 222

Government Accredited with over 140 information partners

We are a government-funded service, providing quality, approved health information and advice

Australian Government, health department logo ACT Government logo New South Wales government, health department logo Northen Territory Government logo Government of South Australia, health department logo Tasmanian government logo Victorian government logo Government of Western Australia, health department logo