MedlinePlus Medical Encyclopedia: Blackheads (comedones)

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Blackheads (comedones)

Blackheads, or open comedones, are common in acne. Clogged hair follicles reflect light irregularly to produce this black hue.

Update Date: 4/14/2008

Updated by: Michael Lehrer, M.D., Department of Dermatology, University of Pennsylvania Medical Center, Philadelphia, PA. Also reviewed by David Zieve, MD, MHA, Medical Director, A.D.A.M., Inc.

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