Chemical Peels (Deep Peels)

* Chemical peels are somewhat effective for ice pick scars but work best for boxcar and rolling scars.

A chemical peel is a mixture of chemicals applied to the skin to strip away the top layers of the skin. The goal is to cause a controlled injury and trigger the body’s natural healing process. As the skin rebuilds, it will produce more collagen and elastin (proteins naturally found in the deeper layers of the skin), which should improve the appearance of acne scars once healing is completed.¹

Chemical peels differ in how deep they penetrate into the skin. Stronger peels penetrate deeper into the skin and can provide better results, but also carry a higher risk of side effects.¹ Chemical peels fall into three types based on how deep they penetrate into the skin.

Deep peels remove the entire epidermis, the papillary dermis, and about half of an even deeper skin layer called the reticular dermis, and thus can treat even deeper scars^1-3.

When it comes to treating acne scars, light peels are not very effective. In general, medium-depth or deep peels are necessary to see significant improvement in the appearance of scars.²

With light and medium-depth peels, multiple (3-6) treatments spaced out at intervals of 2-3 weeks are often necessary to achieve the desired effect.^4-7 With deep peels, a single treatment is sufficient.^8,9

CAUTION: People with dark skin need to approach medium-depth and deep chemical peels with caution because these peels carry a significant risk of skin pigmentation changes, such as prolonged skin darkening (hyperpigmentation).¹⁰

As with all scar revision treatments, chemical peels are sometimes combined with other scar revision procedures to achieve desired results.

People with active acne should not undergo acne scar repair of any kind, including chemical peels. Make sure your skin is clear of acne before beginning scar treatment.

Before agreeing to undergo treatment with a chemical peel, ask multiple doctors about their opinions, proposed treatments, expected outcomes, and prices.

Procedure details:

The chemicals used in chemical peels are usually different types of acids, which corrode (eat away at) the skin when they are applied to the skin surface. For light peels, doctors use weak acids or low concentrations of strong acids. For deeper peels, stronger acids and/or higher concentrations of acids are used.

Deep peels contain one of the following chemicals:^1,3,10

• TCA (trichloroacetic acid) in high concentrations of 50% or higher*
• Phenol in various concentrations**

* TCA (trichloroacetic acid) is the “gold standard” of chemical peel treatments–in other words, it is the most common and most frequently recommended chemical peel for acne scars. This is because, if applied correctly, a TCA peel provides the best balance of high efficacy and relatively low side effects. TCA can act as a light, medium-depth, or deep peel depending on the concentration: the higher the concentration, the deeper the peel. After the application of a TCA peel, a characteristic white “frost” appears on the skin.¹⁰ Today, TCA is often applied using a new technique called CROSS (Chemical Reconstruction Of Skin Scars).

**CAUTION: Phenol is toxic to the body. When phenol is absorbed by the skin, it can enter the bloodstream and travel to the heart and other organs, where it can cause serious damage.^2,11 Phenol-based peels require careful monitoring of the heart and lungs and are therefore not as popular as other types of peels.¹ Approach phenol-based peels with caution and only consider undergoing treatment with these peels under the care of a very experienced physician.

Anesthesia:

Deep peels are painful and normally require anesthesia or at least sedation. Doctors use one or more of the following types:

• An injection of a sedative into a vein (intravenously).
• An injection of an anesthetic into a facial muscle (intramuscularly).
• General anesthesia^3,9

Before-and-after:

Acne scars before (left) and 6 months after (right) treatment with a deep chemical peel.