Urea and sodium chloride in moisturisers for skin of the elderly--a comparative, double-blind, randomised study

Urea has long been used to treat dry skin. In the present report, we compared two identical creams, with the exception that one contained both urea and sodium chloride and the other urea alone, in 23 healthy elderly subjects. Following a 2-week wash-out, their clinically non-eczematous, rough- or normal-appearing skin on the anterior proximal part of the lower legs was treated twice daily in a double-blind and randomised manner. We examined the treated areas by measuring transepidermal water loss, capacitance and electrical impedance. Our findings suggest that both moisturisers seem equally effective, at least concerning the ability to reverse impedance indices towards normal, an effect ascribed to changes in hydration of the stratum corneum. However, the relevance of the impedance parameters to the clinical picture is disputable and further studies of moisturisers in elderly subjects are needed.