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Diseases and Conditions
Pityriasis roseaFrom MayoClinic.com
Special to CNN.com
Pityriasis rosea is a common skin condition in children and young adults. It usually begins as one large spot on your chest, abdomen or back and then spreads. The rash of pityriasis rosea often sweeps out from the middle of the body, and its shape resembles drooping pine-tree branches.
Although pityriasis rosea has a distinctive appearance once the rash appears, in its early stages you may confuse pityriasis rosea with other skin disorders, such as ringworm or eczema.
The cause of pityriasis rosea is unclear, but it may be the result of a virus. Pityriasis rosea usually goes away on its own within six to eight weeks. In the meantime, you can take steps to relieve the discomfort.
Signs and symptoms
Characteristics of pityriasis rosea include:
The exact cause of pityriasis rosea is unclear, although the cause may be a viral infection, such as certain strains of the human herpes virus (HHV6 or HHV7).
When to seek medical advice
See your doctor if you develop any of the following signs:
Also contact your doctor if you've been diagnosed with pityriasis rosea, and the rash doesn't go away within three months.
Pityriasis rosea can cause severe itching, especially if you become overheated.
The rash usually fades without leaving any permanent marks. But, if you have dark skin, long-lasting flat, brown spots may remain after the rash has healed.
Screening and diagnosis
If your doctor suspects you have pityriasis rosea, he or she will do a physical exam, inspecting the spots that have appeared on your skin. Often, this exam is all it takes to diagnose pityriasis rosea.
In its early stage, however, pityriasis rosea can look like several other skin diseases, including ringworm, eczema, psoriasis or secondary syphilis. Your doctor may order blood tests or a skin biopsy to rule out these conditions.
In most cases, pityriasis rosea goes away in four to eight weeks. Treatment usually focuses on controlling itching. The antiviral drugs acyclovir and famciclovir and the antibiotic erythromycin may reduce the duration of pityriasis rosea to one to two weeks. These medications often are not necessary, however, because itching is usually mild, and the condition clears up on its own.
If itching is a problem, your doctor may recommend the following to provide relief:
These steps may help relieve the discomfort of pityriasis rosea:
April 03, 2006