Hello, I am Eva Wilson. Glycolic acid is a powerful alpha hydroxy acid that exfoliates and brightens the skin. It can be used at home, in conjunction with the Renewal Kit at the clinic to remove dead skin cells and boost collagen production for a more youthful-looking complexion. Glycolic acid isn’t gentle so it’s important not to use this product on the face every day; we recommend using it once or twice per week (a product guide will be included with your kit).