Pityriasis Rosea
What is this spreading rash?
Pityriasis rosea is a skin rash that usually begins with one large patch on the skin that quickly spreads to many small widespread patches. Often times patients will notice the first large spot on the skin. This is called the herald patch. It usually is pinkish in color and has a ring of scale or dry skin on it. Shortly after, usually within one to two weeks, many smaller spots will start to appear on the body. These too will look pink in color and sometimes have that same dry or scaly appearance. It is often seen most commonly on the trunk (back, chest and abdomen) but sometimes does reach to the neck, arms and legs. Sometimes these spots can be itchy.
No one knows for sure what causes pitryiasis rosea. We do know that it is not contagious. One theory is that pityriasis rosea can be triggered by a virus, but this has never been proven. It is not caused by a bacteria or fungus on the skin.
Pityriasis rosea does not usually require treatment. This skin rash will go away on its own, but it may take 6-8 weeks or more for it to disappear completely. If it is itchy, topical creams and anti-histamines can be prescribed to help make you feel more comfortable.