Maintaining a youthful appearance through the rehabilitation of photoaged skin is a topic of growing interest among the general population. To meet this need, rejuvenation techniques such as chemical peeling, dermabrasion, and laser resurfacing have been developed. Of these, chemical peeling has the longest record of safety and efficacy while being an easily accessible modality to the clinician. Chemical peeling is also low in cost and has a relatively quick recovery time.1
Chemical peeling is the result of application of a chemical agent to the facial skin to create an injury to a specific depth, thereby inducing rejuvenation via wound repair. The degree of tissue penetration and ensuing injury by the peeling agent is dependent on several factors including skin preparation, anatomic site, duration of peeling, and the strength of the compound.1 The depth of the injury is used to classify chemical peels into several categories. Superficial chemical peels cause epidermal injury. Medium-depth chemical peels cause injury to the level of the upper dermis. Deep chemical peels cause injury that extends to the level of the mid-dermis.
Chemical peeling has been practiced since ancient times. Cleopatra was known to use an alpha hydroxyacid (AHA) (lactic acid) from sour milk to smoothen her skin. Of historical interest to dermatology, Unna first described the use of trichloroacetic acid (TCA), salicylic acid, resorcinol, and phenol in 1882. Mackee, in 1903, treated facial scars with phenol and began publishing his results in 1952. In the 1940s, Eller and Wolff summarized the peeling formulas available at that time and used phenol, resorcinol, salicylic acid, and carbon dioxide (CO2).2 In the 1960s, Brown, Baker, and Gordon described a modified phenol solution with Septisol, croton oil, and water while Ayres began experimenting with TCA.3–6 The work of Stegman in the 1980s characterized the histologic depth of many chemical cauterants and heralded a controlled scientific approach to chemical peeling.7 Van Scott’s work on AHAs in the 1970s and 1980s laid the foundation for the most popular superficial peeling agent, glycolic acid (GA).8
Peels are classified based on the achievable depth of penetration, which determines the clinical effect of the agent. Superficial peels (0.06 mm depth) lead to exfoliation and regeneration of the entire epidermis while very superficial peels only affect the stratum corneum. Medium-depth peels (0.45 mm depth) will destroy the epidermis and induce inflammation within the papillary dermis. Deep peels (0.6 mm depth) will induce inflammation into the reticular dermis and induce new collagen production.7
As with any procedure, patient selection is key to optimizing outcomes and special attention should be paid to features of the patient’s history and physical examination in attempt to identify factors ...