Han, HJ; Park, CW; Lee, CH; Yoo, CW
Background: Aloe vera has been used for medical purposes since antiquity, so it has been known as the healing plant or silent healer. It has been claimed that aloe has several important therapeutic properties including promotion of wound healing, thermal injury healing, anti-inflammation and immunomodulation. Using these effects, it has become an ingredient in a wide variety of cosmetic products including night creams, soaps, shampoos, suntan lotions, and cleansers. Object: In order to investigate the anti-irritant effect of aloe vera we measured transepidermal water loss (TEWL) and erythema index (E-index) after performing a patch test using sodium lauryl sulfate (SLS) and aloe vera we then compared the extent of damaging effect on the skin barriers and the difference of the recovery process in each case. Methods: Fifteen volunteers, all over 18 years of age, who hadn't had past or present history of atopic dermatitis and other eczemas, were tested in this study. SLS was dissolved in distilled water to the concentration of 1% and aloe vera gel was dissolved in distilled water to the concentrations of 10, 20, 50, and 100%. Then we mixed 1% SLS solution and each concentration of aloe vera solution with the ratio 1:1. Each solution was applied to marked sites of both volar aspect of the forearm at random, for 24 hours, using large Finn chamber with filter paper. TEWL and E-index were measured before test (BL) and at 30 minutes (DO), 1st day (D1), 2nd day (D2), 1st week (W1), 2nd week (W2), and 3rd week (W3) after removal of the patches. Results: TEWL after removing a patch of 0.5% SLS was higher than that of 100% aloe vera mixed with 1% SLS. In addition, TEWL after removing a patch of 0.5% SLS and 100% aloe vera patch mixed with 1% SLS were higher than that of 100% aloe vera. E-index after removing a patch of 0.5% SLS was higher than that of 50% aloe vera mixed with 1% SLS, 100% aloe vera mixed with 1% SLS, and 100% aloe vera. Conclusion: We have come to know that aloe vera has an effect in the recovery of skin barriers and erythema induced by irritant such as SLS. However, it only happens when the gel of aloe vera has a high concentration.