Supramolecular Salicylic Acid Alleviates Skin Photoaging by Increasing Collagen Density and Elasticity.

BACKGROUND: Skin rejuvenation has always been of great concern. Although salicylic acid (SA) has multiple properties, it is mainly used in dermatology as a superficial peeling agent that can improve photodamaged epidermis. However, the effect of SA on the photoaging dermis is unclear. PURPOSE: To evaluate the efficacy and safety of supramolecular SA alone for treating photoaged skin, and the effect of SSA on photoaged dermis. METHODS: This is a double-blind, randomized, placebo-controlled trial. 36 patients with photodamaged hands were enrolled. One hand was randomly selected as SSA treated side. 30% SSA biweekly and 2% SSA daily was applied for 4 months; an additional follow-up was performed 2 weeks after the last treatment. Skin photoaging score (SPS), global aesthetic improvement scale (GAIS), viscoelasticity, ultrasound parameters, color and transepidermal water loss (TEWL) were assessed. RESULTS: SSA treatment induced a significant increase in collagen density and skin elasticity, accompanied by an increase in dermal thickness and a decrease in melanin index and TEWL. As result, the GAIS and the SPS were improved significantly after SSA treatment. No adverse events were observed after SSA treatments, and 98% of the subjects were satisfied or very satisfied with the treatment. CONCLUSION: SSA can increase collagen density and skin elasticity to alleviate skin photoaging effectively and safely. LEVEL OF EVIDENCE I: This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266 .