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 color 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 pityriasis alba?
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 look slightly pink. 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 color.
How is pityriasis alba diagnosed?
A doctor usually can tell if you have pityriasis alba just by looking at the patches on your skin. Sometimes a doctor will lightly scrape the surface of the patch to check a few skin cells. This can rule out other problems.
How is it treated?
Pityriasis alba most often goes away without treatment. It may take a few months or longer for the color of the skin to return to normal.
Using a moisturizer or cream 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.
If you're out in the sun, use a sunscreen to protect your skin from too much sun. Choose a sunscreen for sensitive skin.
Habif TP (2010). Atopic dermatitis. In Clinical Dermatology, A Color Guide to Diagnosis and Therapy, 5th ed., pp. 154â€“180. Edinburgh: Mosby Elsevier.
Habif TP (2010). Light-related diseases and disorders of pigmentation. In Clinical Dermatology: A Color Guide to Diagnosis and Therapy, 5th ed., pp. 741â€“775. Edinburgh: Mosby.
Habif TP, et al. (2011). Pityriasis alba. In Skin Disease: Diagnosis and Treatment, 3rd ed., pp. 83â€“85. Edinburgh: Saunders.
Lapeere H, et al. (2012). Hypomelanoses and hypermelanoses. In LA Goldman et al., eds., Fitzpatrick's Dermatology in General Medicine, 8th ed., vol. 1, pp. 804â€“826. New York: McGraw-Hill.
ByHealthwise StaffPrimary Medical ReviewerE. Gregory Thompson, MD - Internal MedicineAdam Husney, MD - Family MedicineMartin J. Gabica, MD - Family MedicineSpecialist Medical ReviewerRandall D. Burr, MD - Dermatology