Potential for Allergic Contact Dermatitis in Popular Hair Care Practices and Ingredients.

The incidence of allergic contact dermatitis (ACD) due to personal care products is rising in parallel with increasing product availability and consumer interest. Hair products specifically represent a significant source of potential allergens, including preservatives, surfactants, emulsifiers, fragrances, adhesives, and dyes. ACD due to hair care products can present as dermatitis in the distinctive "rinse-off" distribution, involving the neck, eyelids, and lateral face in addition to the scalp. Herein, the authors review ingredients in hair care products that can cause ACD and practical tips for allergen identification.