Propylene Glycol, Water, L-Ascorbic Acid, Alcohol, Ascorbyl Glucoside, Fragrance. Propylene Glycol is a colorless liquid that acts as a humectant or delivery agent in skin care products.
Apply five to seven drops of Obagi Professional-C Serum to the face, neck and chest using fingertips. Use on cleansed skin in the morning before sunscreen and makeup application. A slight tingling may occur in some people, which diminishes with continued use.