(pit-uh-RYE-uh-sis ROW-zee-uh) is a harmless skin
rash that is common in older kids and young adults.
More to Know
Pityriasis rosea usually starts with one large, slightly raised patch of scaly
skin on the chest, belly, back, or thighs. As the rash spreads, the original patch
(called a herald patch or "mother" patch) is joined by a number of smaller spots that
spread out across the torso.
In some cases, the spots spread to the arms and legs. These spots are sometimes
called "daughter" patches. They're generally oval and often form a pattern on the
back that resembles a Christmas tree. Both the "mother" and "daughter" patches can
be itchy and scaly, and the rash may sometimes be accompanied by flu-like symptoms.
Doctors aren't sure what causes pityriasis rosea, but it's not due to allergies,
bacteria, or fungi. Most cases of pityriasis rosea go away in 1 to 2 months without
When pityriasis rosea does require treatment, it's usually just to control the
itching. Over-the-counter itch creams, allergy syrups, oral antihistamines, and even
just getting a moderate amount of sunlight can help control itching and treat the
rash. However, hot baths and showers and getting overheated can make the itching worse.
Keep in Mind
Pityriasis rosea is harmless and is not contagious, and usually goes away on its
own. Still, it's important to get it checked out by a doctor to rule out other conditions.
All A to Z dictionary entries are regularly reviewed by KidsHealth medical