Understanding the role of urea in emollient selections

People with diabetes are often prone to dry skin on their feet due to a number of factors, including anhidrosis (the inability to sweat normally) which is commonly associated with diabetic neuropathy.1, 2

Flexitol^® is a urea-based emollient (at 25% urea and 10% urea concentrations) that provides a medically proven regime for dry, cracked heels and feet associated with diabetic anhidrosis.1 Urea is a physiological substance that is widely used across the Flexitol^® range of products due to its highly hydrating and moisturising properties. It is a major constituent of the skin’s Natural Moisturising Factor (NMF) and is widely distributed within human tissue. In some dry skin conditions, urea appears depleted and so Flexitol^® 25% Urea Heel Balm replenishes these levels.

Being inherently hygroscopic, urea hydrates the skin by increasing the water uptake from the dermis layer of the skin and enhances the water-binding capacity of the stratum corneum.

In a double-blind comparative study, 30 outpatients with bilateral anhidrosis applied a 10% urea cream to the right foot and a 25% urea cream to the left foot, twice daily. Results indicate that both creams increased skin hydration levels significantly, with the 25% urea cream showing an increase more than double that for the 10% urea cream.1

1. Baird S, et al. 2003. Anhydrosis in the Diabetic Foot: A Comparison of Two Urea Creams. The Diabetic Foot, Vol. 6 No. 3, 122-36.
2. Lower extremity amputation in diabetic patients. Lund University, Doctoral Thesis, 1994.