Background: Although effective moisturizers can improve xerotic skin changes immediately, their effects are only transient, because the materials applied to the stratum corneum (SC) are easily shed from the skin surface by the daily desquamation process. However, there are a few lines of clinical as well as experimental evidence suggesting that, once application of effective moisturizers is repeated daily, they may produce persistent effects without being influenced by the desquamation of the skin surface. If we can expect such pharmacological effects by simple repeated applications of moisturizers on the skin surface, it will provide a great motivation for the introduction of corneotherapy into the treatment of xerotic skin problems. Objective: This study was designed not only to confirm the feasibility of corneotherapy but to propose a practical method to assess such long-lasting effects of moisturizers by using biophysical methods. Methods: We conducted applications of various moisturizers twice daily to different areas of the flexor surface of the forearms for the initial 5 days of the first week. Thereafter, we performed biophysical measurements of the SC of these areas in the second week, namely 3, 5 and 7 days after their last applications. Results: Daily repeated applications of moisturizers did not induce any change in the water barrier function of the SC or in the size of desquamating corneocytes, a parameter for turnover rate of the SC. However, they substantially increased high-frequency conductance, a parameter for the hydration state of the skin surface, for several days in both normal individuals and patients with atopic xerosis, although the lasting effects were shorter in the latter. The obtained data enabled us to rank the efficacy of moisturizers either according to the duration of the lasting effects or the magnitude of an increase in the hydration levels of the SC. Conclusion: The present results confirmed the feasibility of corneotherapy, in which even simple application of moisturizers targeted at the SC can produce unexpected persistent clinical effects after their repeated treatments. The method described in this study constitutes a practical assay system to evaluate the efficacy of topical agents used for dry skin problems objectively and quantitatively.

Kligman AM: The biology of the stratum corneum; in Montagna W, Lobitz WC (eds): The Epidermis. Orlando, Academic Press, 1964, pp 387–433.
Tagami H: Impedance measurement for evaluation of the hydration state of the skin surface; in Leveque J-L (ed): Cutaneous Investigation in Health and Disease: Noninvasive Methods and Instrumentation. New York, Dekker, 1999, pp 79–111.
Kligman AM: Regression method for assessing the efficacy of moisturizers. Cosmet Toiletries 1978;93:27–35.
Serup J, Winther A, Blichmann WC: Effects of repeated application of a moisturizer. Acta Derm Venereol (Stockh) 1989;69:457–459.
O’Goshi K, Tabata N, Sato Y, Tagami H: Comparative study of the efficacy of various moisturizers on the skin of the ASR miniature swine. Skin Pharmacol 2000;13:120–127.
Hanifin J, Rajka G: Diagnostic features of atopic dermatitis. Acta Derm Venereol Suppl (Stockh) 1980;92:44–47.
Watanabe M, Tagami H, Horii I, Takahashi M, Kligman AM: Functional analysis of the superficial stratum corneum in atopic xerosis. Arch Dermatol 1991;127:1689–1692.
Tagami H, Ohi M, Iwatsuki K, Kanamaru Y, Yamada M; Ichijo B: Evaluation of the skin surface hydration in vivo by electrical measurement. J Invest Dermatol 1980;75:500–507.
Nilson GE: On the Measurement of Evaporative Water Loss: Methods, and Clinical Application; thesis, Linkoping University, 1977, medical dissertation No 48.
Tabata N, Tagami H, Kligman AM: A twenty-four-hour occlusive exposure to 1% sodium lauryl sulfate induces a unique histopathologic inflammatory response in the xerotic skin of atopic dermatitis patients. Acta Derm Venereol (Stockh) 1998;78:244–247.
Hara M, Kikuchi K, Watanabe M, Denda M, Koyama K, Nomura J, Horii I, Tagami H: Senile xerosis: Functional, morphological and biological studies. J Geriatr Dermatol 1993;1:111–120.
Hashimoto-Kumasaka K, Takahashi K, Tagami H: Electrical measurement of the water content of the stratum corneum in vivo and in vitro under various conditions: Comparison between skin surface hygrometer and corneometer in evaluation of the skin surface hydration state. Acta Derm Venereol (Stockh) 1993;73:335–339.
Wigger-Alberti W, Rougier A, Richard A, Elsner P: Efficacy of protective creams in a modified repeated irritation test. Acta Derm Venereol (Stockh) 1998;78:270–273.
Aoyama H, Tanaka M, Hara M, Tabata N, Tagami H: Nummular eczema: An addition of senile xerosis and unique cutaneous reactivities to environmental aeroallergens. Dermatology 1999;199:135–139.
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