Ask An Expert: Seasonal Eczema

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Ask An Expert: Seasonal Eczema

Question:

I had eczema for the first time last fall, at age 22. Now, this spring I have it again. Do seasonal changes affect eczema?

Answer:

Eczema comes in many varieties. Allergic ("atopic") eczema usually starts in childhood, typically by age 7. However, it is possible to have eczema for the first time as an adult. Some types of eczema are more common in adults. One example is nummular eczema, which causes round coin-sized areas of redness and flaking that can be scattered over the limbs and buttocks. The pattern of flare-ups in eczema depends upon your exposure to triggers, how aggressively you treat the skin rash, how aggressively you treat other allergy symptoms, and the severity of your eczema.

For some people, seasonal changes can affect eczema. Low humidity and dry skin can trigger eczema. Some experts think that small cracks in dry skin allow the immune system to be exposed to microscopic bacteria, yeast and debris that are present on everyone's skin. Any of these may activate allergic symptoms.

At the time when allergic rhinitis or asthma is most active, eczema can also be at its most active. Allergic rhinitis and asthma are usually triggered by inhaled allergens in the environment. Dust mites, molds, plants and pollens (common air-borne allergens) are more or less abundant in different seasons. During winter, if a home is sealed for warmth and does not have adequate ventilation, mold and mites are more likely to accumulate.

Some people find that heat or perspiration trigger eczema. Fungal infections such as athletes' foot can trigger some forms of eczema.

Mary Pickett, M.D., is a lecturer for Harvard Medical School and an assistant professor of medicine at Oregon Health & Science University in Portland, OR. At OHSU, she practices general internal medicine and teaches medical residents and students.

Last updated:	May 23, 2007