Serum 20 AOX+

In the morning after cleansing, apply 4-5 drops to a dry face, neck, and chest to promote healthy skin. Apply before other skincare products. May be used on the back of the hands. It is normal for vitamin C products to darken after opening due to air and light exposure. The formula will remain effective. Once opened, it is recommended to be used within 3 months of opening.

Complete your regimen with a SkinCeuticals sunscreen. When used together, SkinCeuticals antioxidants and broad spectrum sunscreens provide more comprehensive protection against visible aging caused by environmental aggressors.

This lightweight antioxidant serum combines 0.2% ferulic acid with a maximum 20% pure vitamin C (l-ascorbic acid) for enhanced antioxidant performance. It is formulated under the Duke Antioxidant patent. Vitamin C is a highly-potent antioxidant that by its structure has difficultly being effectively absorbed by on skin. The Duke Antioxidant patent describes the formulation parameters required for effective delivery of vitamin C to skin: 1) pure l-ascorbic acid (vitamin C); 2) an acidic pH within the 2.0-3.5 pH range and; 3) a concentration between 10%-20%. SkinCeuticals is the only brand to formulate antioxidants according to these parameters.