Anti-Wrinkle Effect on the Outer Corners of the Eyes of a Cosmetic Cream Containing Various Bioactive Ingredients of Kampo Medicines: A Preliminary Clinical Trial with the Split-Face Method

Since the causes of aging are diverse, anti-aging requires a wide range of strategies. Kampo, a traditional medicine of Japan, which has its roots in traditional Chinese medicine, is generally prepared by combining several natural compounds to produce a multiple pharmacological effect, which is considered useful against aging with various changes. In this study, we evaluated the effects of a medical cosmetic Kampo cream on 14 healthy female subjects aged 31 to 59 years with dry skin and shallow wrinkles at the corners of the eyes using the split-face method. The subjects applied the test cream to only one side of their faces twice a day for 4 weeks. Their wrinkles around the eyes on both sides of their faces were evaluated from photographs taken by expert examiners who were blinded to the subjects. The effects on skin condition were also assessed using a questionnaire given to the subjects. Judgments made by the experts from the photos suggest that the wrinkles on the side of the face where the cream was used were improved, while those on the other side were not. The reduction in wrinkles was more pronounced in elder subjects. This reduction in wrinkles on the test side of the face was also supported by the results of the questionnaire administered to the subjects. In addition to wrinkles, many other aging-related parameters such as skin softness, makeup adhesion, smoothness, tightness after washing the face, and moisture were suggested to be improved with the use of the test cream. These results indicate that the application of the Kampo cream for 4 weeks showed an anti-wrinkle effect and the preservation of the facial skin in a healthy condition, which may be due to the combined effects of the natural ingredients used in Kampo medicine.