This is an example of an allergic skin reaction (allergic dermatitis) caused by hair dye. The skin on the neck is red (erythematous), thickened (lichenified), scaly, and crusted.
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.