Definition

Pityriasis rosea is a common skin rash that occurs mainly in children and young adults. The scaly, reddish-pink rash first appears on the back, stomach, or chest. The rash can then spread to the neck, arms, and legs. Pityriasis rosea usually occurs in the spring and fall.

This condition may last for several weeks. Although the lesions usually go away on their own after 2 to 3 months, you should contact your doctor if you experience any of the symptoms below.

Causes

The cause of pityriasis rosea is unknown, although research suggests that it may be caused by viruses or certain medications, such as antibiotics or heart medications.

Risk Factors

A risk factor is something that increases your chance of getting a disease or condition.

The following factors increase your chance of developing pityriasis rosea:

• Age: 10 to 35 (although the condition can occur at any age)
• Time of year: the condition most often occurs in the spring and fall

Symptoms

If you experience any of these symptoms, do not assume it is due to pityriasis rosea. These symptoms may be caused by other health conditions. If you experience any one of the symptoms below, see your physician.

Symptoms include:

• Feeling ill—You may feel like you are getting a cold just before the rash appears.
• Having a “herald patch”—Typically this is the first lesion to appear.
  • It is a large, oval, scaly lesion that typically occurs on the back, stomach, armpit, or chest.
  • After several days, more lesions then appear on the body.
  • Lesions found on the back tend to form a “Christmas tree” pattern.
  • The scale of pityriasis rosea is often described as “trailing scale." It forms inside of the leading pink edge of the the lesions.
• Mild to severe itching of the lesions—The rash of pityriasis rosea is typically not itchy, but itching may occur in some patients.
  • Itching worsens when the body overheats (eg, during physical activities or after taking a hot shower).
• Having skin redness or inflammation
• Feeling tired and achy

If symptoms last for more than three months, contact your doctor.

Diagnosis

Your doctor will ask about your symptoms and medical history, and perform a physical exam, including an examination of your skin. You may be referred to a doctor who specializes in skin disorders (a dermatologist). A dermatologist can usually diagnose pityriasis rosea by examining your skin.

Since the condition can look like other skin disorders, including eczema]]> , ]]>ringworm]]> , ]]>syphilis]]> , and ]]>psoriasis]]> , other tests may be needed to confirm the diagnosis.

Eczema

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Tests may include the following:

• Blood tests
• Skin scrape
• ]]>Skin biopsy]]> —removal of a sample of skin tissue from the lesion to test for pityriasis rosea

Skin Biopsy

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Treatment

There is no cure for pityriasis rosea. The rash will usually go away on its own after several weeks. The symptoms of pityriasis rosea, such as itching, can be relieved using different treatments. Talk with your doctor about the best treatment plan for you. Treatment options include the following:

Prevention

Because the cause of pityriasis rosea is unknown, there is no way to prevent it. It is not contagious and rarely reoccurs after you have had it. There are no permanent marks left after the lesions disappear. However, some people with dark skin may experience skin discoloration that usually fades with time.