UREA-CONTAINING MOISTURIZERS INFLUENCE BARRIER PROPERTIES OF NORMAL SKIN

Moisturizers are used in the treatment of dry skin, both clinically an d in cosmetic products, In the present study the influence of differen t moisturizers on the normal skin barrier properties was evaluated by measuring transepidermal water loss (TEWL) and skin capacitance, In ad dition, the skin reactivity to a topically applied surfactant, sodium lauryl sulphate (SLS), following the use of the moisturizers was exami ned, The skin reaction was assessed visually and by measuring TEWL and superficial blood flow Treatment with two urea-containing moisturizer s for 10 and 20 days decreased TEWL, The irritant reactions after expo sure to SLS were also significantly decreased after prior treatment fo r 20 days with the urea-containing moisturizers. In a double-blind veh icle-controlled part of the study, urea was found to decrease the skin susceptibility to SLS after only three applications, However, this de crease in skin reactivity was not preceded by a reduction in TEWL. Ski n capacitance increased after three applications of urea-containing mo isturizers and was still increased after 10 days, but not after 20 day s of this treatment, Treatment for 20 days with two moisturizers witho ut urea did not influence either TEWL or the susceptibility to irritat ion from SLS, but it increased the skin capacitance significantly, The mechanism underlying these changes is not known, The lower degree of SLS-induced irritation in the skin treated previously with urea-contai ning moisturizers may be of clinical relevance in reducing contact der matitis from irritant stimuli.