Glycolic acid peels are a popular rejuvenation treatment for discolored, scarred or damaged skin. Understanding how glycolic acid peels work provides essential information about the benefits and effects of treatment. Glycolic acid is a commonly used hydroxy acid, favored for its commercial availability and versatility. Glycolic acid can be buffered to reduce its burning effects and combined with hydrating agents such as hyaluronic acid or added to facial cleansers to supplement peeling procedures. The concentration of glycolic acid in a product differs depending on skin type and among over-the-counter and professional treatments. Glycolic acid peels offer a gentle alternative to resurface skin, as weekly applications can provide a cumulative benefit with reduced effects that allow damaged skin to slowly be replaced with new tissue.
Significance
Alpha hydroxy acid (AHA) is one type of chemical peel used in cosmetic and dermatologic treatments. Glycolic acid is an AHA that is derived from fruit and sugar cane. It is water soluble and the smallest molecule of AHA, which enables it to penetrate the top layer of skin (epidermis). Glycolic acid has a pH of around 2.5 and is available in varying concentrations or strengths between 10 percent and 70 percent. It is an effective peel that stimulates exfoliation and new skin growth to reduce the appearance of fine lines, especially on the face and hands.
Action
Glycolic acid dissolves the bonds that hold the top layer of skin cells in place to induce epidermolysis (peeling of loosened skin). It also stimulates collagen production in the dermal cells, which improves tissue hydration, resulting in a smoother texture as the skin regenerates. The peeling and stimulating effects of glycolic acid peels are more pronounced with dosage and frequency of use.
Benefits
The effects of glycolic acid peels are directly proportional to concentration and duration of application. The higher the concentration or strength of glycolic acid, the deeper the agent penetrates the skin layers. Consequently, stronger applications of glycolic acid cause more peeling and are left on the skin for a short period of time. Peeling resurfaces the skin because old, tougher skin is shed and newer skin is exposed. This provides benefits in reducing wrinkles and fine lines, minimizing scars and pigmented patches and opening pores. Peeling is induced within hours after treatment and may continue for several days.
Side Effects
Possible side effects associated with skin treatment are caused by irritation, including excessive dryness, infection, itching, swelling and redness in treated areas. The newly exposed skin may have a lighter or uneven pigmentation than surrounding skin. Generally, these side effects stabilize as treatment progresses and can be alleviated with topical ointments such as moisturizers or soothing gels. Sensitivity to sunlight is a side effect of most skin treatments, including AHA peels, when new dermal layers are exposed.
Warnings
Glycolic acid peels can be administered weekly for up to eight weeks. Prolonged application of a glycolic acid peel should be monitored because it can cause burns or irritation. The FDA guidelines for over-the-counter or cosmetic formulations of glycolic acid peels limit the concentration to 10 percent to reduce risk of burns. Commercially available products containing glycolic acid include a warning about AHAs increasing sun sensitivity and a recommendation to use sunblock.