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Atopic Dermatitis (Eczema)


The Manual's Editorial Staff

Last full review/revision Sep 2019| Content last modified Sep 2019
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What is atopic dermatitis (eczema)?

"Derm" within a word means it has to do with the skin. "Itis" means inflammation. So dermatitis is inflamed skin.

Atopic dermatitis, also called eczema, is a long-term type of dermatitis that usually runs in families. It causes a patchy rash that makes your skin itchy, red, scaly, and dry.

  • Eczema is very common, especially in children—most people get it before age 5

  • It's more common in people who have food allergies, hay fever, or asthma and usually runs in families

  • It's treated with medicines put on the skin and by avoiding things that make it worse

  • Eczema usually goes away or gets better as you get older

What causes eczema?

Doctors don’t know what causes eczema, but it runs in families.

People who have asthma, hay fever, or food allergies have a higher chance of having eczema. Eczema can’t be spread from person to person.

Many things can trigger your eczema or make it worse:

  • Stress

  • Changes in temperature or humidity

  • Skin infections from bacteria

  • Dust mites, molds, and dander

  • Some kinds of makeup

  • Clothes that rub on your skin, especially wool

  • For babies, sometimes food allergies

What are the symptoms of eczema?

The symptoms of eczema are different for babies compared to children and adults.

For babies with eczema, the rash:

  • Is red, oozing, crusty, and itchy

  • Starts on the face and spreads to their neck, scalp, hands, arms, feet, and legs

  • Can cover large areas of their bodies

  • May last for several months before improving

For children and adults with eczema, the rash:

  • Itches a lot

  • Usually shows up in only one or a few spots, especially your hands, upper arms, in front of your elbows, behind your knees or around your eye

  • Can flare up again and again, usually in the same places

If you have eczema, your skin may get thick where you scratch it a lot. Scratching your open skin can lead to infections.

How can doctors tell if I have eczema?

Doctors can diagnose eczema by looking at the rash and asking you about your personal and family health history.

How do doctors treat eczema?

Doctors can’t cure eczema, but to help with your symptoms, they may suggest that you:

  • Apply medicines, such as corticosteroid and other creams to lessen itching and heal your skin

  • Keep your skin moist with cool water compresses, lotions, petroleum jelly, or vegetable oil after baths or showers

  • Take a bath or shower only once a day to keep your skin from getting dry

  • Take a bath in water with a small amount of bleach, colloidal oatmeal (a product made of finely ground oatmeal), or tar medicine

  • Blot your skin dry after a bath or shower instead of rubbing it dry

If your eczema is severe, your doctor may prescribe corticosteroid pills or other medicines that slow down your immune system.

If you're an adult, your doctor may try phototherapy. With phototherapy your skin is exposed to a special ultraviolet light (similar to lights used for tanning). Doctors usually don't use phototherapy on children or adolescents with eczema.

How can I prevent eczema from getting worse?

To help prevent eczema from getting worse:

  • Avoid scratching

  • Use moisturizers to keep your skin from getting dry

  • Avoid things that irritate your skin

  • Avoid foods that you’re allergic to

  • Avoid sweating and very hot or cold temperatures

  • Wear light cotton clothes and avoid wool and other rough fabrics

  • Use a humidifier in the house to keep the air moist

  • Try to lower your emotional stress

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