Issue link: https://www.ascpskindeepdigital.com/i/70637
before after Hyperpigmentation and acne on an African-American client, before and after treatment with a chemical peel. Images courtesy of Pamela Springer. Perform a skin analysis using a skin scope or Wood's lamp. Black light can illuminate a variety of conditions. Dark spots, or PIH, will have a fluorescent appearance, signaling that the melanin deposits may be mostly epidermal. If the lesion is dermal, it may not respond to the black light. The use of these tools will also help you evaluate how dry or oily the skin is. After assessing the skin's overall condition and noting any unusual problems, discuss what the client is most interested in correcting, taking into consideration both the analysis and the client's own input. Preparing the Skin The outcome of a chemical peel is determined by how well the skin has been prepared. For darker skin, the concern is avoiding PIH. Peels that penetrate too deeply can generate heat or erythema (redness) while on the skin, potentially altering melanin synthesis and/or causing abnormal melanin distribution. Deep penetration can also destroy the melanocyte, leaving an area of the skin void of color. To decrease this risk, the client should be placed on a pretreatment home-care regimen for four to eight weeks (depending on how dark the skin is) prior to a scheduled light- or medium-depth peel. During this time, the goal is to either repair the acid mantle or to perform other treatments that will enhance the outcome of the peel. If the acid mantle is intact, the home-care regimen should consist of a skin- lightening agent, 2–5 percent glycolic products, and a full-spectrum sunscreen. There should be visible reduction of dyschromias after two to three weeks of the home-care regimen. Priming the skin in this manner will go a long way toward eliminating post-peel complications. Common Skin-Lightening Agents It is important to know the mechanism of action when using skin- lightening agents. First and foremost, you must know the cause of the hyperpigmentation. This will determine the selection and management of the lightener to be used. ARBUTIN Studies have shown that arbutin is less effective than kojic acid for treating pigment disorders. It is not recommended as a priming product for light- to medium-depth peels. HYDROQUINONE This is the most effective agent on darker skin types, although its use is controversial due to the potential for adverse effects. It is one of the only inhibitors of melanogenesis. The mechanism of action is to inhibit tyrosinase activity, the enzyme that plays a major role in producing pigmented cells. A 2 percent formulation will provide visible improvement within four to six weeks, with the amount of improvement reaching a plateau after three to four months. The duration of use should be a maximum of four months, followed by a six-month break before any subsequent use. KOJIC ACID In concentrations from 1–4 percent, kojic acid prevents the melanocytes from being able to transfer pigment to the keratinocyte. Although effective as a skin-lightening gel, kojic acid has high sensitivity potential, and may also cause irritant contact dermatitis. 14 ASCP Skin Deep July/August 2012