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Learn more.Product Details
Serum 20 AOX+ is formulated with the precise concentration of 20% vitamin C that has been proven to provide maximum environmental protection and anti-aging benefits. This facial serum neutralizes free radical damage that contribute to atmospheric skin aging – environmental damage and premature signs of aging caused by free radicals from UVA/UVB. In addition to antioxidant benefits, this facial serum improves the appearance of fine lines and wrinkles.
- Neutralizes free radicals induced by environmental aggressors
- Reduces the appearance of fine lines and wrinkles
- Paraben-, fragrance-, alcohol-, and dye-free
- Ideal for normal, oily, and combination skin types
How To Use

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.
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Science & Proof

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.
Key Ingredients
- 20% L-ascorbic acid
- 0.2% ferulic acid
Lauded for its superior antioxidant benefits, this highly potent form of pure vitamin C helps neutralize free radicals and protect against oxidative stress while providing visible anti-aging benefits.
Learn more about L-ascorbic acidSee all ingredients
aqua / water / eau, ascorbic acid, ethoxydiglycol, propylene glycol, glycerin, zinc sulfate, phenoxyethanol, sodium hydroxide, panthenol, ferulic acid, sodium hyaluronate
Physician Insight

This serum is loaded with great antioxidant benefits as it contains 20% L-ascorbic acid.
Dr. Joseph Terracina - The Skin Institute
Learn about Dr. Joseph TerracinaComplete Your Regimen
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