What is Eczema?

Dermatitis also known as eczema is a long-lasting (chronic) skin condition. It’s most common in babies and children, but adults can have it, too. Or, the skin may stay dry and get irritated easily. In adults it tends to come and go for a long time.

People with atopic dermatitis may lack certain proteins that maintain the skin’s barrier to water. This can cause the skin to be very sensitive to irritants and more likely to get skin infections caused by bacteria, viruses, or fungus.


The most common symptoms of atopic dermatitis are:

  • Dry, itchy skin (itching may begin before the rash appears)
  • Raw, red skin with blisters that weep clear fluid or crust over—caused by scratching
  • Rashes on the face, inside the elbows, behind the knees, and on the hands and feet
  • Thickened areas of skin from long-term scratching

When to See a Doctor

Call your healthcare provider if:

  • Symptoms do not get better with the care you give at home.
  • The treatment your healthcare provider recommends does not work.
  • You show signs of an infection—such as red and painful skin.

You should not get the smallpox vaccine if you have atopic dermatitis. It could cause a serious reaction.


The exact cause of atopic dermatitis is not known. It does not spread from person to person, and you cannot “catch” it.

Atopic dermatitis appears to be linked to both genetic (inherited from parents) and environmental factors. It’s more common in children whose parents have asthma or allergies. About 1 in 3 children with atopic dermatitis also have food allergies. People who live in cities or in dry climates are also more likely to have eczema.

People with eczema may find that common products, situations, or even foods cause the condition to flare up. These are sometimes referred to as “triggers.” Knowing your triggers can help you control your symptoms. Common eczema triggers include:

  • Soaps and household cleaners
  • Fragrances in perfumes and lotions
  • Wool and polyester fabrics
  • Pet dander
  • Cigarette smoke
  • Emotional stress
  • Sweating

Diagnosis and Tests