In a chemical peel, a chemical solution is applied to the skin and allowed to soak in. Over the next 1 to 14 days, depending on how deeply the chemical penetrated the skin, the skin peels off. This procedure destroys parts of the skin in a controlled way so that new skin can grow in its place. The chemicals used are sometimes called exfoliating or wounding agents.The types of chemical peels differ based on how deeply the chemical penetrates and what type of chemical solution is used. Factors that may affect the depth of a peel include the acid concentration in the peeling agent, the number of coats that are applied, and the amount of time allowed before the acid is neutralized. Deeper peels result in more dramatic effects as well as higher risks, increased pain, and longer healing time. There are three basic types of peels:
* Superficial peels are
the mildest type of chemical peel and can be used on all skin types. Superficial
peels usually use liquid containing a mild (dilute) acid, most often glycolic
acid. Dry ice (solid carbon dioxide) is sometimes used.
* Medium peels penetrate the skin more deeply than superficial peels and cause a second-degree burn of the skin. Trichloroacetic acid (TCA) is the main peeling agent used for medium peels, though the peel may also be done in several steps using a different chemical solution followed by TCA.
* Deep peels penetrate several layers of skin and cause a second-degree burn of the skin. They are used only on the face. A chemical called phenol is usually used for a deep peel. Deep peels may not be used on darker skin types because they tend to bleach the skin (hypopigmentation). Even in lighter-skinned people, phenol peels-or any type of deep resurfacing-may bleach the skin. A deep peel can be done only once in most cases.
Before the peel
Your doctor can help you decide what depth of peel and what type of chemical solution is most appropriate, based on your skin type, which areas you want peeled, what kind of results you want, how much risk you are willing to take, and other issues. A small "test spot" may be peeled to get a better idea of the results, especially for people with darker skin.
Two to three weeks before the peel, you will need to begin preparing your skin by cleansing it twice a day, applying a special moisturizer or cream once or twice a day, and using sunscreen every day. In some cases, daily use of tretinoin (Retin-A), a topical medicine usually used to treat acne, is also recommended and may speed healing. This skin care regimen will help the skin peel more evenly, speed healing after the peel, and may reduce the chance of infection and other complications, especially uneven color changes in the skin.
For medium and deep peels of the face, you may be given a short course of medicine (such as acyclovir) to prevent viral infection. This is especially likely if you have had cold sores before, and the peel will be in the areas near the mouth or eyes.
How a superficial peel is done
Right before the peel, the skin is cleaned. The chemical (usually a liquid or paste) is then applied to the skin with a small brush, gauze, or cotton-tipped applicators. The chemical is left on the skin for several minutes, depending on the type of chemical used. Water or alcohol may be used to neutralize the acid and end the chemical reaction, then it is wiped off. You may feel a little burning while the chemical is on your skin. A handheld fan can help cool the skin and relieve any discomfort.