Clinical Study on Itching Relief Caused by Dry Skin of Cosmetics Containing Ceramide NP and Guaiazulene in Smart Healthcare Products

Abstract

In order to effectively treat atopic dermatitis (AD), the restoration of the skin barrier abnormalities and immunologic abnormalities should be carried out together in smart healthcare products. In this study, the anti-inflammatory effect of guaiazulene (GAZ) was confirmed by measuring the expression level of pro-inflammatory cytokines, interleukin 6 (IL-6) and interleukin 8 (IL-8) in tumor necrosis factor‐alpha (TNF‐α) stimulated human keratinocyte cell line, HaCaT cells. Based on the in vitro anti-inflammatory properties of GAZ, cosmetics containing both ceramide NP (CER NP) which has a significant effect on skin barrier function and GAZ were developed and clinical trials were conducted on the effects of itching relief caused by dry skin by measuring skin moisture content, transepidermal water loss (TEWL), and visual analog scale (VAS). As a result, (1) In the skin moisture content, the rate of change after 2 weeks and 4 weeks of test products use statistically significantly increased by 89.804% and 91.980%, respectively, compared with before test products use; (2) In the TEWL, the rate of change after 2 weeks and 4 weeks of test products use statistically significantly decreased by 11.026% and 9.938%, respectively, compared to before test products use; (3) In the VAS grade, the rate of change after 2 weeks and 4 weeks of test products use statistically significantly decreased by 66.191% and 83.944%, respectively, compared with before test products use. This study proved the outstanding clinical effect of the cosmetics containing 2% CER NP and 0.02% GAZ on itching relief caused by dry skin.KeywordsClinical studyItching reliefCeramide NPGuaiazuleneCosmeticsSmart healthcare