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PREPRINTS OF THE 1999 ANNUAL SCIENTIFIC SEMINAR 117 FORMULATING FOR THE UNIQUE ATTRIBUTES OF MATURE SKIN Zoe Diana Draelos, M.D. Dermatology Consulting Services, High Point, NC 27262 Introduction The skin undergoes constant change, adapting to environmental stresses, the cumulative effects of ultraviolet (UV) radiation, and hormonal fluctuations. These changes become more pronounced with maturity, creating formulation challenges in this age group. This paper discusses the unique attributes of mature skin in hopes of aiding in the formulation of efficacious products for this expanding population segment. Data 1. Artatomic and Physiologic The pertinent data collected regarding age related cutaneous differences in physiology and functioning is presented in tabular form. The data is also compared for various races. EVALUATED CAucASIA• ' HISPANIC SKIN" ASIAN BLACK SKIN'" MATURE SKII• PARAMETER SKIN' SKIN' SC THICKNESS 7.2 MICRONS 6.S MICRONS EPIDERMIS BECOMES MORE COMPACT WITH AGE SC LAYERS 17 22 NO CHANGE TEWL FOLLOWING HIGHER THAN " HIGHER THAN LOWER IN HEALTHY SLS EXPOSURE TM WHITE FOLLOWING WHITE FOLLOWING AGED SKIN 2% SLS PREOCCLUDED SKIN 0.5% SLS TEWL FOLLOWING HIGHER THAN HIGHER THAN NO CHANGE TAPE STRIPPING WHITE WHITE CORTICOSTEROID HIGHER PERMEATIOI • LOWER PERMEATIDI NO CHANGE PENETRATION •' THAN BLACK THAN WHITE VESSEL REACTIVITY HIGHEST SAME AS WHITE LESS NO AGE-RELATE D SKIN DIFFERENCE STINGING GRI•,•TEST POSSIBLY LESS POSSIBLY LESS SUSCEPTIBILITY , ,, MELANOGENESIS DECREASED EXFOLIATION DECREASED ABILITY ABILITY TO HEAL DECREASED AND WITHSTAND TRAUMA RESPONSE TO"' 'ERYTHEMA ERYTHEMA HYPER- POSSIBLY' LESS IRRITATION AND HYPER- PIGMENTATION PIGMENTATION •WEAT GLAND-• FENNER APOCRINE- MOR E APOCRINE- NO CHANGE ECCRINE GLANDS ECCRINE GLANDS CERAMIDE LEVELS v' INTERMEDIATE INTERMEDI•TE"HIGH HIGHEST ' ' LOWEST DECR•ASE'D wITH AGE