Nummular eczema is an allergy-related disorder in which itchy, coin-shaped spots or patches appear on the skin.

Eczema - nummular; Nummular dermatitis

The cause of nummular eczema is unknown, but there usually is a personal or family history of:

• Allergies
• Asthma
• Atopic dermatitis

It is relatively uncommon, and most often occurs in elderly men.

Several things may make the condition worse, including

• Dry skin
• Environmental irritants
• Stress
• Temperature changes

• Coin-shaped skin lesions
  • On the arms and legs
  • May spread to middle of body
  • Ooze and become crusty
• Itching
• Scaly or raw skin
• Skin redness or inflammation

Your doctor can usually diagnose this condition by looking at your skin and asking you about your family's medical history.

A skin biopsy may be needed to rule out other similar conditions.

Avoid triggers that can make your symptoms worse, such as wool, lanolin, and certain foods. Experts do not recommend taking frequent baths - excess bathing and soaps can cause dry skin, which often makes the condition worse.

Your doctor may recommend skin lotions, soaps, or moist bandages to soothe scaly, dry, or healing areas. Antihistamines taken by mouth may relieve itching.

Persons with severe symptoms may be given prescription skin ointments that contain tar, corticosteroids, or immunosuppressive drugs. In rare, severe cases, the doctor may prescribe more powerful corticosteroids to be taken by mouth or injection.

Nummular eczema is a long-term (chronic) condition. Medical treatment and avoiding irritants can help reduce symptoms.

A secondary infection of the skin may develop.

Call your health care provider if you have symptoms of this condition.

Also call for an appointment with your health care provider if:

• Symptoms continue despite treatment
• You have signs of infection (such as fever, redness, or pain)

There is no known way to prevent the disorder. Avoid any triggers that make your symptoms worse.

Morelli JG. Eczematous disorders. In: Kliegman RM, Behrman RE, Jenson HB, Stanton BF, eds. Nelson Textbook of Pediatrics. 18th ed. Philadelphia, Pa: Saunders Elsevier;2007:chap654.