There is no mention of pityriasis pruriens in the clinic generally, but generally refers to pityriasis rosea. The development reason of pityriasis rosea in the clinical among, actually at present is not very clear. Patients occur pityriasis rosea, generally seen in adults, like children as well as the elderly is uncommon. The patient in the early time, often will find a light red red spot in their own trunk position, above will be attached obviously fine scale distribution, this is the so-called mother spot. And after 1-2 weeks, patients can find themselves in other parts of the trunk, the extremities will occur some area is obviously smaller than the mother spot, rose-colored plaques, above will often also be distributed fine scales, and patients will often be accompanied by different degrees of itching. But the pityriasis rosea often after 4-8 weeks is able to fade by itself.