What is pityriasis rosea? — Pityriasis rosea is a harmless skin rash that causes small, itchy spots on the belly, back, chest, arms, and legs. The rash usually lasts about 4 to 6 weeks, but in some people, it can last for months.
Pityriasis rosea is most common in older children and young adults.
What causes pityriasis rosea? — The cause is not known. But it does not seem to be easily spread from person to person.
What are the symptoms of pityriasis rosea? — In many people, the rash starts with one round or oval patch. This spot is about the size of a half dollar but might be larger. A day or two later, many smaller spots about the size of a dime appear. But not everyone gets the large spot before the rest of the rash.
If you have light skin, the spots are usually pink or salmon-colored. If you have dark skin, the spots can be a red-brown color or darker than your skin and .
The spots might be:
On the belly, back, chest, arms, and legs
Spread out in a "Christmas tree" pattern on the back
A little scaly
In children, the spots sometimes happen on the face and scalp.
Is there a test for pityriasis rosea? — Maybe. Your doctor or nurse will often be able to tell if you have it by learning about your symptoms and doing an exam. But he or she might gently scrape the rash or do a different test to get a sample of your skin. Tests on the skin sample can help the doctor tell if you have pityriasis rosea or a different disease.
Is there anything I can do on my own to feel better? — Yes. You can:
Take a special kind of bath called an oatmeal bath. Use lukewarm, not hot water.
Use unscented moisturizing lotion or cream on your skin.
Keep your body cool.
How is pityriasis rosea treated? — Most people do not need any treatment. If the symptoms bother you, your doctor might prescribe creams or ointments to help with itching. In rare cases, doctors prescribe other medicines or a special type of treatment that uses lights, called "phototherapy."
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This topic retrieved from UpToDate on: Mar 30, 2020.
Topic 17226 Version 5.0
Release: 28.2.2 - C28.105
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