Glycolic peels are mild peels. They do not penetrate very deeply into the skin so they do not typically cause wounds. For this reason they are some of the safest peels. They are best to treat surface imperfections, for example, light skin discolorations, freckles, acne/blackheads. Glycolic acids also stimulate collagen building, so over time multiple glycolic peels may help with very fine wrinkles and acne scarring. 

Most patients who get glycolic peels get a series of them every 2-4 weeks for 4 treatments, and periodically repeat that sequence. Because they are mild, the results after each treatment are subtle but over time can make a big difference.