A compound formed in the liver from ammonia produced by the deamination of amino acids. It is the principal end product of protein catabolism and constitutes about one half of the total urinary solids. [PubChem]
10% hydrate skin
15% accelerate fibrin degradation
20-30% are antipruritic, break down keratin, decrease the thickness of the stratum corneum and are used in scaling conditions such as ichthysosis
40% are proteolytic and may be used to dissolve and peel dystrophic nails
[Patient Self Care, 2010]
As a humectant, urea draws water into the striatum corneum.