Surg Cosmet Dermatol. 2009;1(1):5-9
Objectives: The objective of this study was to evaluate the effects of different concentrations of urea on skin moisture.
Institution: A double blind, randomized, placebo-controlled study was conducted at the Medcin Instituto da Pele – Clinical Research Center –, in Osasco, SP, Brazil.
Material and methods: Individuals with dry skin were submitted to one application of three different concentrations of a urea moisturizer, namely 3%, 5%, and 10%, and a control moisturizer. Clinical, subjective, and corneometry measurements were evaluated at 1, 4, and 6 hours.
Results: All moisturizers, including the control emulsion, improved significantly the skin moisture in the first evaluation (p < 0.05); 10% urea was superior to other concentrations, especially at the 4-hour evaluation, when it was compared with 3% urea,
and at the 6-hour evaluation, when compared with the 5% and 3% presentations; at the 1-hour evaluation, patients referred itching and stinging with the use of 10% urea moisturizer.
Conclusion: The duration of the hygroscopic properties of urea is directly related with its concentration. Adverse symptoms, such as stinging, were observed only with higher concentrations.
Keywords: UREA