Pityriasis alba (say "pih-tih-RY-uh-sus AL-buh") is a common skin problem that causes round or oval patches of skin that look lighter than the rest of the skin. The patches may look pink or slightly scaly at first.
How the patches look may bother you, but they aren't harmful. Over time, the patches fade and the colour of your skin returns to normal.
This skin problem is most common in children. But anyone can get it. The patches may be more noticeable in people with darker skin.
What causes it?
The cause of this skin problem is not known. But it may be related to sun exposure or dry skin.
What are the symptoms?
Pityriasis alba usually doesn't cause symptoms. In some cases, it may be itchy.
It causes slightly scaly, round or oval patches on the skin. The patches may look slightly pink at first. Later they fade to leave areas that are lighter than the other skin. They most often appear on the face, neck, upper arms, or upper part of the body. It may take some time, but the skin will return to its normal colour.
How is it diagnosed?
A doctor usually can tell if you have pityriasis alba just by looking at your skin. To rule out other problems, a light called a Wood's lamp may be used to look more closely at your skin. Or your doctor may lightly scrape the surface of the patch to check a few skin cells.
How is pityriasis alba treated?
Pityriasis alba most often goes away without treatment. It may take a few months or years for the colour of the skin to return to normal.
Using a moisturizer, cream, or petroleum jelly can help relieve dry skin. If itching is a problem, talk to your doctor about what medicine might work best. Your doctor may suggest steroid creams. These can help if the skin is itchy or irritated.
Protect your skin from the sun. For example, stay out of the sun during midday hours, use a broad-spectrum sunscreen, and wear sun-protective clothing.
Medical Review:E. Gregory Thompson MD - Internal Medicine & Adam Husney MD - Family Medicine & Martin J. Gabica MD - Family Medicine & Randall D. Burr MD - Dermatology
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