Pityriasis rosea (pit-ih-RYE-uh-sis ROE-zee-uh) is a harmless temporary skin condition
that's common in older kids and teens. This pink or gray scaly skin rash can last
for 4 to 8 weeks — or, sometimes, months. The rash usually starts with one big
patch on the chest, abdomen, thighs, or back that's often mistaken for ringworm.
As the rash spreads, the original 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 (however, it usually doesn't appear on the palms or soles). The spots can be
Pityriasis rosea is not contagious. Although sometimes the spots take a while to
fade completely, most kids have no lasting traces of the rash after it's healed.
What Causes Pityriasis Rosea?
Doctors aren't really sure what causes pityriasis rosea. Some think it's caused
by a virus, but this hasn't been proved.
Pityriasis rosea is more likely to show up in the spring and fall.
What Are the Signs & Symptoms of Pityriasis Rosea?
Most kids and teens who get pityriasis rosea have no warning signs. Others can
have flu-like symptoms (a sore throat, swollen glands, headaches, or feel tired) a
few days before the rash appears.
The rash itself usually starts with one large spot, called the herald patch
or "mother" patch, which can appear anywhere on the skin but usually is on the chest,
abdomen, back, or thighs. This patch can be raised and may feel scaly. In people with
light skin, the patch is pink or red. People with darker skin can see a variety of
colors, from violet to brown to gray.
The herald patch might be the only sign of this condition for up to 2 to 3 weeks.
As the rash grows, however, smaller spots (called "daughter" spots) can appear across
the torso and on the arms and legs. The spots look almost identical on both sides
of the body. These small patches are usually oval shaped and often form a pattern
on the back that looks like a Christmas tree.
How Is Pityriasis Rosea Diagnosed?
To diagnose pityriasis rosea, the doctor will examine your child's skin to look
for the telltale signs of the rash. Sometimes doctors gently scrape off a few scales
from the rash to examine under the microscope to rule out other possible causes, like
ringworm or psoriasis.
How Is Pityriasis Rosea Treated?
Most cases of pityriasis rosea go away in 1 to 2 months without any treatment.
Some cases can be as short as 2 weeks, while others can last for 3 months or longer.
When pityriasis rosea does need treatment, it's usually just to control the itching.
Over-the-counter itch creams or allergy syrups can help, and so can oatmeal baths.
In some cases, just getting a moderate amount of sunlight can help improve the
rash and the itching. If your child uses this form of therapy, make sure he or she
is protected from sunburn, which can sometimes make a rash worse.
Light therapy might be prescribed for cases where the itching is really bothersome.
Usually, this involves ultraviolet B (UVB) therapy and is done by a dermatologist.