OverviewBlackheads, or open comedones, are common in acne. Clogged hair follicles reflect light irregularly to produce this black hue.
Review Date 7/25/2017
Updated by: David L. Swanson, MD, Vice Chair of Medical Dermatology, Associate Professor of Dermatology, Mayo Medical School, Scottsdale, AZ. Also reviewed by David Zieve, MD, MHA, Medical Director, Brenda Conaway, Editorial Director, and the A.D.A.M. Editorial team.