Superficial chemical peels have a relatively low complication rate in patients with darker skin types when performed appropriately, a study published in Journal of the American Academy of Dermatology has found.
While chemical peels have been shown to be effective for treating acne, photoaging, and pigmentary dyschromias, few studies have evaluated the occurrence of side effects, particularly in patients with darker skin, so researchers in Boston undertook a retrospective analysis to determine the frequency and range of side effects following the use of a range of chemical peels for different conditions in this patient group.
They reviewed consecutive adult patients with skin types III to VI who received a chemical peel of the face, upper extremities, hands, axillae, back, abdomen, buttocks or lower extremities for melasma, post-inflammatory hyperpigmentation (PIH), acne, acanthosis, lentigines or photoaging from August 2012 through March 2017. The chemical peels applied included 35-70% glycolic acid (GA), 88% lactic acid (LA), 40% mandelic acid (MA), 10-30% salicylic acid (SA) and 15% tricholoracetic acid (TCA). Some patients received combination peels which involved layering of two different acids.
All peels were undertaken by a single dermatologist at Boston Medical Center, and before the acid was applied the skin was prepared with Neutrogena® Ultra Gentle foaming cleanser and 70% isopropyl alcohol to remove all debris. Approximately 2.5mL of acid was applied with firm pressure to the skin using a cotton gauze, and any open lesions were avoided. A portable fan was used to help cool the skin and reduce any burning sensation.
For all single agent peels with glycolic acid (n=199, 42.1%), lactic acid (n=7, n=1.5%) or mandelic acid (n=42, 8.9%), and all combination peels with glycolic acid, lactic acid or mandelic acid (n=175, 37.0%), sodium bicarbonate was applied to the affected area after two to twelve minutes to neutralize the acid. The time varied according to the patient’s tolerance of the chemical peel; if patients developed intolerable burning at any point during the procedure, the acid was immediately neutralized and/or removed.
Repeat peels were performed no sooner than two weeks later, and the strength of the acid used and/or the contact time was increased in patients who had tolerated the chemical agent with no side effects during the initial peel and had shown some improvement in their condition.
Iced cotton gauze was used to remove all peeling agents, and this was left on the treated area for several minutes and then triamcinolone 0.025% cream or ointment was applied to reduce inflammation; the cream was used for patient who had acneiform lesions in the treated area, and the ointment for all other patients.
Patients were provided with Neutrogena® Ultra Gentle cleanser and instructed to use it daily on the treated area. They were told to avoid harsh skin treatments and avoid sunlight for 48 hours after the peel, and after that to apply a sunscreen with sun protection factor (SPF) 30+ before any sun exposure.
In total 473 chemical peel treatments were performed on 132 patients with skin types ranging from III to VI; of which 198 were given for melasma, 129 for PIH, 10 for acne, 98 for more than one diagnosis, and 37 for other indications. Most of the treatments were performed on women (82%) and to the face (80.1%). The majority of patients had a single agent peel (n=296; 62.6%), and the most common was 35% glycolic acid (n=89, 18.8%).
Three quarters of patients (75.5%) reported that the peel had a positive impact on their skin condition, and only 18 treatments (3.8%) were associated with side effects and these had a median duration of 4.5 weeks.
Lead author Dr Shalini Vemula of the Department of Dermatology, Boston University School of Medicine, Boston, MA, said: “Overall, superficial chemical peels have a relatively low complication rate in darker skin types. However, people with darker skin (Fitzpatrick skin type VI) are more likely to experience side effects when exposed to chemical peels. The most common side effects are crusting and hyperpigmentation.”
The study found that the most frequent complications were prolonged crust (2.3%), PIH (1.9%) and erythema (1.9%). Blistering and post-inflammatory hypopigmentation each occurred in one patient (0.2% each), and no treatments resulted in folliculitis or exacerbation of the patients’ existing dermatologic conditions. Patients with skin type VI had significantly higher odds of side effects (OR, 5.14; 95% confidence interval [CI], 1.21-21.8; P=0.0118).
“All side effects occurred in patients that had a chemical peel on their face for an underlying pigmentary disorder, such as melasma or post-inflammatory hyperpigmentation. None of the patients who had a chemical peel with 40% mandelic acid had side effects,” Vemula added.
Adverse events were most frequently reported with lactic acid (14.3%), followed by glycolic acid 35% (6.48%), and salicylic acid 20% (5.17%). Side effects were less likely when peels performed in the winter; by season, side effects were mot frequent in the spring (n=8, 6.0%), followed by fall (n=5, 4.6%), then summer (n=4, 3.8%) and winter (n=1, 0.8%).
Asked how dermatologists can minimise the risk of side effects when performing chemical peels in patients with skin of color, senior author Dr Neelam A. Vashi, an assistant professor and Director of both the Boston University Center of Ethnic Skin and Boston University Cosmetic and Laser Center at Boston University School of Medicine, said: “It is important to cleanse the skin thoroughly prior to application of the chemical peel and to apply the same amount of pressure to the entire face while applying the peel. In addition, iced gauze and low to medium potency topical steroids immediately after a chemical peel can be helpful in minimizing the risk of potential side effects. It is also important to provide patients with strict aftercare instructions, including cleansing with a gentle cleanser, avoiding harsh skin treatments and avoiding sun exposure in the days following a chemical peel.”
Vashi added: “When dermatologists perform chemical peels in a standardized manner, superficial chemical peels have a relatively low complication rate in skin of color patients.”
1. Vemula S, Maymone MBC, Secemsky EA, Widjajahakim R, Patzelt NM, Saade D, Vashi NA, Assessing the Safety of Superficial Chemical Peels in Darker Skin: A Retrospective Study, Journal of the American Academy of Dermatology (2018), doi: 10.1016/j.jaad.2018.02.064.