Atopic Dermatitis Eczema - Managing Your Allergies: Allergies

Content provided by the Faculty of the Harvard Medical School

Atopic dermatitis (eczema)

Atopic dermatitis is an itchy rash that usually appears first in childhood. The itch promotes scratching, which leads to further irritation and an increased rash. In early childhood the rash is found mainly on the back of joints. In adults it is usually limited to one area of the body, such as the hands.

Atopic dermatitis may be worsened by allergies to certain foods — milk, eggs, soy, wheat, or peanuts, for example — or airborne allergens. Many children with eczema go on to develop allergic rhinitis and allergic asthma. This progression, called “the allergic march,” probably has a genetic basis, because close to 50% of people with atopic dermatitis can point to a family history of allergic diseases.

Diagnosing and treating atopic dermatitis

The condition can be diagnosed from the appearance of the rash and the response to treatment. RAST testing — and skin testing for mild cases — may help to identify triggers.

Treatment involves avoiding triggers, if they can be identified, and managing the disorder. Management includes soothing the ferocious itch with salves and cool compresses, hydrating the dry skin, and applying anti-inflammatory creams and ointments. The skin in allergic dermatitis is a poor barrier and loses water easily. Rehydrating the skin — by soaking in the bath, using hydrating creams and ointments, or both — is an essential part of treatment. For severe flare-ups, you may need to soak more than once a day, following with applications of sealing dressings or creams to keep the moisture contained. Petroleum jelly (Vaseline) works well.

Emollients with a low water content applied immediately after a bath or shower help to lock in the moisture. Thick creams, such as Nutraderm, Eucerin, Vanicream, Cetaphil, or even shortening do a good job. Get creams without fragrances and preservatives, and buy them in 1-pound jars — you may need a lot! Emollients with a high water content that evaporates contribute to dry skin and can cause a flare-up. Because they are effective barriers, apply emollients at different times of day than you use anti-inflammatory creams.

Topical corticosteroids reduce inflammation. There are many prescription and over-the-counter preparations to choose from. Although they are effective, a major drawback is that potent steroids cannot be used on the face — where symptoms often appear — because they gradually thin the skin and cause small blood vessels to break. Two newer medications, tacrolimus (Protopic, an ointment) and pimecrolimus (Elidel, a cream), have proved effective in lessening the need for corticosteroids and they can be used on the face.

Scratching to relieve the intense itch not only doesn’t bring relief, but can lead to bacterial infections requiring a course of antibiotics. In fact, in a significant proportion of people with atopic dermatitis, a bacterium, Staphylococcus aureus, can make the problem worse and require specific treatment with antibiotics.

Last updated:	August 21, 2006
Reviewed By:	Faculty of Harvard Medical School