what are properties of chemical peels

Superficial chemical peels

Apart from peel treatments, topical agents and aesthetic treatments such as microdermabrasion can also result in superficial peeling; however, the peeling effects can be mistaken for flaking skin or sensitivity. In order to ensure adherence, especially in the early stage of treatment, it is essential to have an adequate medical consultation. Patients should be educated on the expected effects of a chemical peel. In-clinic treatments, which involve an array of topical ingredients, are often required to achieve a true epidermal peel.


1. Hydroxy acids

For more than 40 years, alpha hydroxy acids (or AHAs) have been used as a peeling agent and topical preparation. Discovered at about the same time as vitamin A, alpha hydroxy acids are sometimes referred to as fruit acids. AHAs are often perceived as natural products, as they are produced from nuts, dairy products and fruits. Based on a research by Beradesca et al, alpha hydroxy acids are able to separate the stratum corneum without interrupting the barrier functions. Consequently, it confers protection against 5% sodium lauryl sulphate without altering the TEWL (or trans-epidermal water loss). Being 1 of the most common AHAs, glycolic acid has been shown to reverse photoaging.

Alpha hydroxy acids exert their actions by reducing corneocyte cohesion and damaging desmosomal attachments between the corneocytes. Apart from the peeling effects, AHAs also improve the behavior of elastic fibers and enhance collagen density. Plus, they help to increase glycosaminoglycans and dermal thickness. These unique properties are not observed in other mechanical or chemical exfoliators, which simply remove the outer layer of epidermis.

Formulated with strengths of up to 70%, glycolic acid peels strike an optimal balance between safety and effectiveness. More importantly, the pH of the peels helps maintain an optimal level of depth and penetration. This ensures the effectiveness of the peels and successful treatment. A lot of superficial peels are partially buffered or neutralized during the manufacturing process. While this reduces the stinging sensation, the effectiveness of the peels can also be greatly reduced. To achieve efficacious and safe treatment outcomes, neutralize the glycolic acid peels at a suitable time to stop the peeling effects and penetration. This allows for a better control of the degree of peeling and depth.

Some brands of glycolic acid peels include SkinTech and Dermaceutic. Aside from that, there are an array of “high-street” peels such as NeoStrata, Murad, and Agera, all of which have a high pH. In addition to these brands, there are many other cosmeceutical and cosmetic brands that offer glycolic acid peels. Having hydrating properties, lactic acid is milder than other potent alpha hydroxy acids such as glycolic acids and mandelic acids. Through metabolism, it is converted into lactate (a naturally-occurring hydrating component) in the body. Available in various strengths, lactic acids are incorporated in chemical peels such as gloTherapeutics lactic 15%. A 50% preparation is also available.


2. Resorcinol

Derived from phenol, resorcinol is traditionally used as a peeling treatment. Commonly prescribed for the treatment of pigmentation, resorcinol has been used for more than 150 years. It is believed that resorcinol disrupts the hydrogen bonds in the keratin to exert its actions. Due to its side effect profile, resorcinol is usually used in conjunction with other peels such as Jessner’s peels. Some of the common side effects of resorcinol are cardiac arrhythmia, thyroid dysfunction, and myxedema. In order to minimize the risk of undesirable effects, allergy testing should be conducted prior to the treatment.


3. Retinoic acid

Typically used in topical preparations, Vitamin A is available in an array of dosage strengths (from mild formulations to prescription-only high dose preparations). There are 3 major types of retinoic acid: Retinal, retinol (vitamin A), and retinoic acid (tretinoin or vitamin A1). Retinoic acid is a vitamin A acid while retinal is an aldehyde.

Topical preparations of retinoids can be used for treating acne and sun damage. Being the bioavailable form of vitamin A, retinols are transformed into retinoic acid in the dermal layer of the skin. The effectiveness and safety of vitamin A peels have been proven through numerous studies. According to 1 of the studies, the effects of a 1% tretinoin peel is comparable to topical tretinoin (used topically for 4 to 6 months). In this study, researchers applied the 1% tretinoin peel on 15 female patients, aged 23 to 40 years, with Fitzpatrick skin types 1 to 4 for 6 to 8 hours. Peels containing Vitamin A can also be used in combination with other peeling agents for synergistic effects. For instance, Vitamin A peels are known to enhance the desquamating effects of glycolic acid and salicylic and acid peels.


4. Jessner’s solution

Jessner’s solution (and the modified formulation) are excellent exfoliators that have been used for more than 100 years. Traditionally, Jessner’s solution contains a mixture of 14% lactic acid, 14% salicylic acid, and 14% resorcinol. The modified preparation consists of 8% citric acid, 17% lactic acid, and 17% salicylic acid. Due to its keratolytic effects, Jessner’s solution is commonly used in conjunction with TCA and AHA peels.


5. Beta hydroxy acids

Being the most frequently-cited BHA (or beta hydroxyl acid), salicylic acid is lipophilic in nature. Therefore, the compound is usually used on acne prone, oily skin. Having comedolytic actions, Salicylic acids are capable of penetrating into the sebaceous glands and hair follicles. Salicylic acid is available under many different brands such as Jan Marini, Priori, ZO Skin Health, NeoStrata, Medik8, Cosmedix, Mene & Moy, and Epionce. Once applied, the salicylic acid peeling solution produces a frost on the skin. Do not confuse this with a precipitated dermal protein or epidermolysis.


6. Combinations

Designed to suit different individuals, some peels or protocols contain a combination of various peeling ingredients. The common combinations include:

  • ZO 3-Step Stimulation Peel, consisting of lactic acid, salicylic acid and glycolic acid;
  • NeoStrat protocols, which combine citric acid or mandelic acid with glycolic acid and a home daily peel with N-acetyl Tyrosinamide and glycolic acid;
  • Agera, containing lactic acid, l-ascorbic acid, and salicylic acid;
  • Skin Tech Easy Droxy Versicolour, which contains salicylic acid, lactic acid, glycolic acid, kojic acid, and citric acid;
  • Skin Tech Easy Phytic Peels, containing lactic acid, glycolic acid, mandelic acid, and phytic acid;
  • SkinCeuticals protocols, which consist of resorcinol salicylic acid and glycolic acid.