Clinical evaluation of 40% urea and 12% ammonium lactate in the treatment of xerosis

Background: Urea and ammonium lactate are used for the treatment of xerosis, with different degrees of success. This study compares the clinical effectiveness of these two agents.

Objective: To compare the effectiveness and tolerance of a 40% urea topical cream (Carmol 40) from Doak Dermatologics, a subsidiary of Bradley Pharmaceuticals, Inc., and 12% ammonium lactate topical lotion (Lac-Hydrin 12%) from Westwood Squibb, a division of Bristol-Myers Squibb.

Methods: A randomized, double-blind, bilateral paired comparison study was conducted involving 25 men and women who were undergoing treatment for moderate to severe xerosis. The study included evaluations upon initiation of the study, after a 14-day treatment period and treatment follow-up on day 28.

Results: Eighteen study participants completed the entire 28-day evaluation period. Evaluation of treatment benefit was based on instrumental measurement of water loss from the skin surface, skin capacitance, skin desquamation, skin roughness, subject self assessment of skin and investigator evaluation. Results indicated that clinical observation ratings by patients and investigators, as well as instrument measures, show differences between the two treatments. Most measures show that improvement is achieved in less time with 40% urea cream than with 12% ammonium lactate lotion. On day 14, the 40% urea cream was superior to the 12% ammonium lactate lotion as measured by skin roughness, fissure reduction, thickness and dryness.

Discussion: At day 14 of treatment, 40% urea cream was superior to 12% ammonium lactate for most of the instrumental and clinical assessments.