Urea isn’t just suitable for dry and cracked skin. It can also be used to treat skin conditions like eczema and psoriasis.
Understanding Urea in Dermatology
Urea is a common ingredient in popular skincare products. You’ll find it in face creams, hand creams, and heel balms. But it’s not just a miraculous moisturiser for the cosmetics industry. Dermatologists (skin doctors) routinely prescribe urea to their patients.
According to a 2020 article, urea “represents an old molecule still very useful in dermatology and not replaceable with other substances, because of its unique moisturising, keratolytic and antimicrobial properties that are exerted in a dose-dependent manner.”
In fact, it’s commonly used in eczema, psoriasis, and conditions associated with thickened, dry skin (e.g., keratosis pilaris, calluses and corns, and ichthyosis).
Urea and Eczema
Eczema, or atopic dermatitis, is an inflammatory skin condition where the skin barrier isn’t as strong as it normally is. Specifically, a protein called filaggrin is weaker than normal, preventing the skin from acting as a protective barrier.
People with eczema may notice a build-up of dead skin cells, higher-than-normal loss of moisture, and frequent skin breaks.
Urea acts as both a mild exfoliant and humectant:
1. Its keratolytic effects break down the scaly skin caused by the build-up of skin cells. This leaves the skin more exposed but can help with the absorption of emollients. When it’s used in corticosteroid creams, for example, it allows the dry to penetrate deeper than it can alone.
2. Its humectant effects, on the other hand, help retain moisture within the skin. Urea is hygroscopic, drawing moisture from the second layer of skin (the dermis) and the area, holding it at the surface. This prevents the breaking of the skin and reduces inflammation.
A 2017 review on moisturisers for eczema found that urea-containing creams showed significant improvements in dryness, reduced flare-ups, and were more effective than a placebo for overall skin health.
Urea and Psoriasis
Psoriasis is another inflammatory skin condition where skin cells grow and multiply quickly. As the cells build up, the skin develops thick, scaly, itchy plaques. People with psoriasis may notice inflammation and redness around the plaques.
Depending on the concentration, urea can have different effects on the skin. At the lowest concentrations, the urea primarily acts as a humectant by drawing moisture from the dermis or the air and retaining it in the outer layers of the skin. However, for people with psoriasis, scaly skin requires higher concentrations. Not only will this soften the skin, but it will also break down the psoriasis scales.
In higher concentrations (20-30%), urea acts as a keratolytic, meaning it dissolves excess keratin that contributes to the thick, rough scales. These actions help to shed the built-up skin cells, reducing the thickness of the plaques and making the surrounding skin less itchy.
Urea and Other Skin Conditions
Different conditions will require different concentrations of urea, however. For example, dealing with a specific area of callused skin may require a 25% urea concentration; for nail disorders, it could be 30% or more. However, urea for xerosis of the face may be in the 5-15% range, depending on the severity.
If in doubt, speak to your doctor for further guidance. They can advise on the current concentration and formulation for your skin condition.
Potential Side Effects of Urea Treatment
Urea is generally very well tolerated. Because the body naturally produces it, it’s rare for people to experience any side effects of using urea. Certain higher concentrations may lead to mild irritation. But this should be short-lived, and you can always swap to a lower concentration.
Urea is widely used with other skin treatments, such as corticosteroids and emollients. As mentioned, it may improve the action of some agents.
