Stability, transdermal penetration, and cutaneous effects of ascorbic acid and its derivatives.

Topically applied antioxidants exert their benefits by offering protection from damaging free radicals and over-the-counter cosmeceuticals incorporating antioxidants are among the most popular anti-aging products available. One potent antioxidant of particular note, vitamin C, has been extensively utilized because it possesses a variety of other cutaneous benefits including photoprotection from UV A & B, neocollagenesis, inhibition of melanogenesis and improvement of a variety of inflammatory skin disorders. However, the instability of this water-soluble vitamin, together with difficulties associated with its topical delivery, has presented issues for the formulation chemist. This article reviews the scientific data and clinical studies that underpin the stability, percutaneous absorption, and cutaneous effects of vitamin C together with its commonly utilized, commercially available derivatives.