I discovered this myself when I was about 12 years old: sunlight cleared up the rash on the insides of my elbows. More recently I've had itchy skin after spending too much time in chlorinated pools. Both natural sunlight and tanning beds clear up the itching for me. So I was delighted to find that phototherapy is a standard treatment for dermatitis.
Dermatitis is a general term for skin inflammation. Symptoms typically include itch, redness, and swelling. There are three main categories of dermatitis, depending on the cause:
1. Allergic contact dermatitis. The most common type is to poison ivy, poison oak and poison sumac. Other common allergens include rubber, metals, acrylates (used in artificial nails, eyeglass frames, dental resins and industrial adhesives), pine resin (used in mascara), sunscreen ingredients, hair dyes, dyes used in clothing and cosmetic ingredients.
2. Irritant dermatitis. This is similar to allergic contact dermatitis, but not a true allergic reaction. Irritants include detergents, chlorine, wool and synthetic fibers.
3. Atopic dermatitis. The cause is unknown, but genetic factors are thought to play a role. Individuals with this condition also have an increased risk of hay fever or asthma. Reference one estimates that 90 percent develop skin symptoms before age five. Atopic dermatitis is very common, affecting up to 20 percent of children. Roughly 60 percent continue to experience symptoms in adulthood. Atopic, allergic, and irritant dermatitis can all affect the same person.
The first step in treating skin rash is to work with a dermatologist to identify allergens and irritants. These should obviously be removed from the patient's environment as efficiently as possible. However, atopic dermatitis does not have a specific environmental cause, so further treatment will be necessary in most cases.
Phototherapy provided by dermatologists uses UV light in either the A or B bands, which are reported to be equally effective. Sometimes an oral medication is used to increase the skin's sensitivity to light. The mechanisms of UV light's benefits are still under investigation.