Pityriasis rosea is a skin disease that produces oval spots (papules) over the trunk. The rash is frequently preceded by a "herald patch" (pictured here) lasting 1 to 2 weeks. The rash is usually rose red to brownish red with fine scales and central clearing. Itching (pruritus) occasionally occurs. Spontaneous remission occurs in 2 to 8 weeks. It is probably caused by an infectious agent, most likely a virus.
Linda Vorvick, MD, Medical Director, MEDEX Northwest Division of Physician Assistant Studies, University of Washington School of Medicine. Also reviewed by David Zieve, MD, MHA, Medical Director, A.D.A.M., Inc.