Pityriasis rosea is a mild, common skin condition that produces an itching rash. Its cause is unknown -- it does not seem to be the result of a bacterial or fungal infection or an allergic reaction. It may be viral in nature, but it is not contagious and does not usually recur once it has cleared up.
Signs of Pityriasis Rosea
This disease begins with a single patch of rash, often referred to as a mother or herald patch. The mother patch is about one to four inches across, circular or oval in shape, and is raised and scaly. It can be pink, brown, or other colors, depending on the original skin color. Sometimes instead of a single original patch, there are two smaller patches.
The single patch remains for about two weeks, and then smaller daughter patches spread across the body. They can appear anywhere but rarely spread to the face, palms, soles or scalp. They often form a triangular pattern like a Christmas tree on the back. In some cases, the daughter patches form without any mother patch preceding them.
In about half the cases, the patches itch slightly. The itching may become more intense if the skin is hot, such as after a workout. Pityriasis rosea is also sometimes accompanied by flulike symptoms, such as a headache, sore throat, and nausea.
The rash usually lasts about 6-8 weeks and then fades. It may leave spots on the skin, but those eventually fade as well.
Who Gets Pityriasis Rosea?
While anyone can develop pityriasis rosea, it is most common in pregnant women and people between the ages of 10 and 35. Older people rarely develop it. While pityriasis rosea is not a serious condition, a pregnant woman should still inform her doctor as soon as the mother patch appears.
Treatment for Pityriasis Rosea
Since the cause is unknown, there is no treatment for pityriasis rosea. If the itching is severe enough to be bothersome, a dermatologist may prescribe medicines to help. Depending on the severity of the condition, normal skin lotions, moisturizers, over-the-counter anti-itch creams and antihistamines may be enough. Exposure to sunlight can help the rash clear up more quickly.