Erythema Nodosum

Erythema nodosum is a type of skin inflammation that is characterized by the sudden onset of tender, red nodules on the skin, typically on the lower legs.

What is Erythema Nodosum?

Erythema nodosum is a form of panniculitis, which is an inflammation of the subcutaneous fat. It is a relatively common condition that can affect anyone, but it is more commonly seen in women than men. The exact cause of erythema nodosum is often unknown, but it is thought to be related to an immune system reaction.

Symptoms of Erythema Nodosum

The symptoms of erythema nodosum can vary from person to person, but common symptoms include:

  • Tender, red nodules on the skin, typically on the lower legs, but can also occur on the arms, face, and neck
  • Nodules are usually 1-5 cm in diameter and can be painful to the touch
  • Redness and swelling of the affected area
  • Fever, fatigue, and joint pain may also occur in some cases
  • Symptoms can last for several weeks, but usually resolve on their own within 6-8 weeks

Causes of Erythema Nodosum

The exact cause of erythema nodosum is often unknown, but it is thought to be related to an immune system reaction. Some possible triggers include:

Treatments for Erythema Nodosum

Treatment for erythema nodosum usually focuses on relieving symptoms and addressing any underlying causes. Common treatments include:

  • Rest, elevation, and compression of the affected area to reduce swelling and pain
  • Pain relief medications such as acetaminophen or ibuprofen
  • Corticosteroids to reduce inflammation
  • Colchicine to reduce inflammation and prevent new nodules from forming
  • Potassium iodide to reduce inflammation and promote healing
  • Antibiotics if an underlying infection is suspected
  • Stopping any medications that may be triggering the condition

Complications of Erythema Nodosum

In rare cases, erythema nodosum can lead to complications such as:

  • Permanent scarring or skin discoloration
  • Infection of the affected area
  • Arthritis or joint pain that persists after the nodules have resolved
  • Underlying conditions such as inflammatory bowel disease or cancer may be uncovered during the diagnostic process

Diagnosis of Erythema Nodosum

Diagnosis of erythema nodosum is usually made based on a physical examination and medical history. A doctor may also perform tests such as:

Prevention of Erythema Nodosum

There is no sure way to prevent erythema nodosum, but reducing the risk of underlying infections and avoiding medications that may trigger the condition can help. Additionally, maintaining a healthy lifestyle, including a balanced diet and regular exercise, can help to boost the immune system and reduce the risk of developing erythema nodosum.

Frequently Asked Questions (FAQs)

What is Erythema nodosum?
A type of skin inflammation.

What are the symptoms of Erythema nodosum?
Red, painful lumps on the skin, typically on the legs.

What causes Erythema nodosum?
Infection, medication, or underlying medical condition.

Is Erythema nodosum contagious?
No.

How is Erythema nodosum diagnosed?
Physical exam and medical history.

What is the treatment for Erythema nodosum?
Rest, elevation, and medication to reduce inflammation.

Can Erythema nodosum be prevented?
No, but underlying causes can be treated.

Is Erythema nodosum a sign of an underlying condition?
Yes, often associated with other medical conditions.

How long does Erythema nodosum last?
Typically 2-6 weeks.

Can Erythema nodosum recur?
Yes, in some cases.

Article last updated on: 25th June 2025.
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