clinical features. The essential clinical features are the following: Discrete circular or oval lesions, Scaling on most lesions, and Peripheral collarette scaling with central clearance on at least two lesions. The optional clinical features are the following: Truncal and proximal limb distribution, with less than 10% of lesions distal to mid-upper-arm and mid-thigh, Orientation of most lesions along skin cleavage lines, and A herald patch (not necessarily the largest) appearing at least two days before eruption of other lesions, from history of the patient or from clinical observation. The exclusional clinical features are the following: Multiple small vesicles at the centre of two or more lesions, Two or more lesions on palmar or plantar skin surfaces, and Clinical or serological evidence of secondary syphilis. Treatment The condition usually resolves on its own, and treatment is not required. Oral antihistamines or topical steroids may be used to decrease itching. Steroids do provide relief from itching, and improve the appearance of the rash, but they also cause the new skin that forms (after the rash subsides) to take longer to match the surrounding skin color. While no scarring has been found to be associated with the rash, scratching should be avoided. It's possible that scratching can make itching worse and an itch-scratch cycle may develop with regular scratching (that is, you itch more because you scratch, so you scratch more because you itch, and so on). Irritants such as soaps with fragrances, hot water, wool, and synthetic fabrics should be avoided. Lotions that help stop or prevent itching may be helpful. Direct sunlight makes the lesions resolve more quickly. According to this principle, medical treatment with ultraviolet light has been used to hasten resolution, though studies disagree whether it decreases itching or not. UV therapy is most beneficial in the first week of the eruption. A 2007 meta-analysis concluded that there is insufficient evidence for the effectiveness of most treatments. Oral erythromycin was found to be effective for treating the rash and relieving the itch based on one early trial; however, a later study could not confirm these results. Prognosis In most patients, the condition lasts only a matter of weeks; in some cases it can last longer (up to six months). The disease resolves completely without long-term effects. In a ten-year epidemiological study of 939 people in the United States, less than two percent had a recurrence. Epidemiology The overall prevalence