Chemical peels for acne vulgaris: a systematic review of randomised controlled trials

OBJECTIVE: We evaluated current evidence from randomised controlled trials (RCTs) regarding the effectiveness of chemical peeling for treating acne vulgaris. METHODS: Standard Cochrane methodological procedures were used. We searched MEDLINE, Cochrane Central Register of Controlled Trials and EMBASE via OvidSP through April 2017. Reviewers independently assessed eligibility, risk of bias and extracted data. RESULTS: Twelve RCTs (387 participants) were included. Effectiveness was not significantly different: trichloroacetic acid versus salicylic acid (SA) (percentage of total improvement: risk ratio (RR) 0.89; 95% CI 0.73 to 1.10), glycolic acid (GA) versus amino fruit acid (the reduction of inflammatory lesions: mean difference (MD), 0.20; 95% CI −3.03 to 3.43), SA versus pyruvic acid (excellent or good improvement: RR 1.11; 95% CI 0.73 to 1.69), GA versus SA (good or fair improvement: RR 1.00; 95% CI 0.85 to 1.18), GA versus Jessner’s solution (JS) (self-reported improvements: RR 1.00; 95% CI 0.44 to 2.26), and lipohydroxy acid versus SA (reduction of non-inflammatory lesions: 55.6%vs48.5%, p=0.878). Combined SA and mandelic acid peeling was superior to GA peeling (percentage of improvement in total acne score: 85.3%vs68.5%, p<0.001). GA peeling was superior to placebo (excellent or good improvement: RR 2.30; 95% CI 1.40 to 3.77). SA peeling may be superior to JS peeling for comedones (reduction of comedones: 53.4%vs26.3%, p=0.001) but less effective than phototherapy for pustules (number of pustules: MD −7.00; 95% CI −10.84 to −3.16). LIMITATIONS: The methodological quality of the included RCTs was very low to moderate. Meta-analysis was not possible due to the significant clinical heterogeneity across studies. CONCLUSION: Commonly used chemical peels appear to be similarly effective for mild-to-moderate acne vulgaris and well tolerated. However, based on current limited evidence, a robust conclusion cannot be drawn regarding any definitive superiority or equality among the currently used chemical peels. Well-designed RCTs are needed to identify optimal regimens.