Urea, when used as an ingredient in topical skin applications, aids skin integrity and hydration and exerts keratolytic, antifungal, antibacterial and antipruritic effects. Urea-containing formulations are utilized to treat various dermatological conditions like hand eczema/dermatitis, seborrheic dermatitis and psoriasiform dermatoses of the scalp. 

Two monocentric, simple blind, observational studies examined the efficacy and safety of two urea-containing products in these skin conditions.

Study 1 investigated the effects of a commercially available 30% urea topical cream on hand eczema. It advised the participants to apply the product ≥2/day for 28 ± 2 days. The study assessed transepidermal water loss, skin redness, skin hydration and participant ratings of efficacy and qualities prior to the first product application and on days 14 and 29. 

Study 2 investigated the effects of a commercially available foaming product containing 10% urea on seborrheic dermatitis and scalp psoriasiform dermatoses. It advised the participants to apply the product ≥2/day for 28 ± 2 days. The study assessed the Desquamation index and surface occupied by squames, analyzed extracted squames and microscopically assessed scalp photos and participant ratings of product efficacy and qualities prior to the first product application and on days 14 and 29.

Study 1 observed:

• Enrollment of 20 females.
• A significant decrease in transepidermal water loss, with an increase in the hydration level of the upper skin layers and a decrease in skin redness. 

Study 2 observed:

• Enrollment of 13 females and 7 males.
• A significant decrease in desquamation measures and dryness after the product use.
• The majority of participants in both studies "agreed" or "slightly agreed" that the product had good efficacy and was easy to apply.
• No adverse reactions were observed.

These findings indicate the utility of urea in topically applied vehicles for hand eczema, seborrheic dermatitis and psoriasiform dermatoses.

Source: Celleno L, D’amore A, Cheong WK. The use of urea cream for hand eczema and urea foam for seborrheic dermatitis and psoriasiform dermatoses of the scalp. Clin Cosmet Investig Dermatol. 2022;15:2445-54.