Skinceuticals Retinol 1.0 is formulated for sensitive skin. If your skin is not used to retinol, please begin with Retinol .5. Retinol 1.0 is formulated to be delivered efficiently and effectively to the skin while maintaining it's original molecular structure. SkinCeuticals Retinol 1.0 was designed with highest levels of pure retinol on the market to help your skin stimulate cell regeneration and build collagen. Building collagen helps to diminish the appearance of fine lines, wrinkles, and age spots. They help minimize the appearance of pore size, while correcting blemishes and blotchiness often associated with problematic skin.