Dr. Cole is board certified in dermatology. He obtained his BA degree in bacteriology, his MA degree in microbiology, and his MD at the University of California, Los Angeles. He trained in dermatology at the University of Oregon, where he completed his residency.
Dr. Shiel received a Bachelor of Science degree with honors from the University of Notre Dame. There he was involved in research in radiation biology and received the Huisking Scholarship. After graduating from St. Louis University School of Medicine, he completed his Internal Medicine residency and Rheumatology fellowship at the University of California, Irvine. He is board-certified in Internal Medicine and Rheumatology.
Pityriasis rosea is a common rash usually seen in individuals between 10-35 years of age. The rash typically lasts six to eight weeks, rarely extending 12 weeks or longer. Once a person has pityriasis rosea, it generally does not recur in their lifetime.
Pityriasis rosea characteristically begins as an asymptomatic single, large pink, scaly patch called the "herald patch" or mother patch, measuring 2-10 centimeters. The herald patch is a dry pink to red patch which appears on the back, chest, or neck and has a well-defined, scaly border.
One to two weeks following the initial appearance of the herald patch, a person will then develop many smaller pink patches across their trunk, arms, and legs. The second stage of pityriasis rosea erupts with a large number of oval spots, ranging in diameter from 0.5 centimeter (size of a pencil eraser) to 1.5 centimeters (size of a peanut). The individual spots form a symmetrical "Christmas tree" pattern on the back with the long axis of the ovals oriented in the "Lines of Blaschko" (invisible skin lines of embryonic origin). This rash is usually limited to the trunk, arms, and legs, rarely occurring on the face and neck. Pityriasis rosea usually spares the face, hands, and feet.
Picture of pityriasis rosea on the torso; photo courtesy of Gary W. Cole, MD, FAAD
In those few patients in whom the itching is severe enough to require treatment, there are a number of alternatives. Weak to moderately potent topical steroids and oral antihistamines (many of which are available without a prescription) will suffice. Sometimes ultraviolet light administered in a doctor's office or by careful sunbathing can diminish the itching sufficiently to be tolerable.