Blackheads, or open comedones, are common in acne. Clogged hair follicles reflect light irregularly to produce this black hue.
Review Date 10/31/2016
Updated by: Kevin Berman, MD, PhD, Atlanta Center for Dermatologic Disease, Atlanta, GA. Review provided by VeriMed Healthcare Network. Also reviewed by David Zieve, MD, MHA, Isla Ogilvie, PhD, and the A.D.A.M. Editorial team.