If you’ve recently looked closely at the label on your moisturizer, you may have seen urea listed in the ingredients list.

Urea is included in a variety of cosmetics and skin care products for its moisturizing and exfoliating properties.

The urea used in skin care products is made synthetically in a lab, but urea is also naturally found on your skin and is excreted in urine.

Let’s go over the role of urea in skin care products and take a look at its potential side effects.

The outer layer of your skin is called your epidermis, and it can be divided into five sublayers.

The outermost sublayer, the stratum corneum, keeps unwanted molecules from entering your body and prevents water loss through your skin.

The water-retaining property of the stratum corneum largely comes from a group of substances known as natural moistening factors (NMFs). Among these NMFs are:

  • urea
  • various amino acids
  • lactic acid
  • pyrrolidone carboxylic acid

Urea is used in a variety of skin care products to target general skin dryness or medical conditions associated with dry or itchy skin. Urea can also help exfoliate dead skin buildup and may help target fungal infections.

Moisturizes your skin

According to a 2017 research review, a number of studies have found that dry skin can be successfully treated with creams or lotions containing urea.

Urea is a humectant. This means it keeps your skin moist by drawing water from the deeper layers of your skin and the air.

Exfoliates

Urea is known as a keratolytic agent. This means it breaks down the protein keratin in the outer layer of your skin. This action can help reduce dead skin buildup and get rid of flaking or scaling skin.

The exfoliating actions are strongest in creams containing more than 10 percent urea.

Increases the action of some medications

A 2013 study suggested that urea may help some medications penetrate through your skin. These medications include corticosteroids and antifungal creams.

A 2019 review of studies found that urea enhanced the function of oral and topical antifungal treatments for onychomycosis, which is a fungal infection of the toenail.

However, more research is needed to fully understand its effects.

Urea creams and lotions are used to treat a variety of conditions associated with dry, rough, or scaling skin.

In particular, it’s commonly used to treat conditions of the feet like:

  • calluses
  • corns
  • some nail problems

Urea creams and lotions have been used as a successful treatment for:

Urea creams and ointments appear on the World Health Organization’s list of essential medications for a basic healthcare system. This is due to its:

  • safety
  • effectiveness
  • affordability

According to the Cosmetics Info database, short- and long-term studies have found that even in large doses, urea seems to be safe for topical use with a low risk of side effects.

In some cases, urea may cause mild skin irritation and symptoms like stinging, itching, or burning.

It’s also possible to have an allergic reaction that causes more severe symptoms. If you experience symptoms like trouble breathing or a rapid heartbeat, you should seek medical attention immediately.

Urea may also increase the absorption of some of the other ingredients in the product you’re using. If you’re sensitive to a different ingredient, urea may make your reaction worse.

Urea products are generally not recommended for children under 2 years old. However, a doctor can best advise you whether a urea cream is suitable for your child.

Skin care products can contain anywhere from about 2 percent to 40 percent urea. The percentage that you should use depends on the condition you’re trying to treat.

Urea cream or lotion less than 10 percent

Skin care products that contain less than 10 percent urea primarily act as moisturizers, according to a 2018 review. A cream containing a low dose of urea may be appropriate for treating dry skin or conditions that lead to dry skin.

Between 10 and 20 percent

At strengths above 10 percent, according to the same 2018 review, urea creams and lotions have a keratolytic action, meaning they help exfoliate dry and flaking skin.

You can use 20 percent urea creams to treat conditions like:

  • rough patches of skin
  • calluses
  • cracked heels

Higher than 20 percent

Urea products with a concentration higher than 20 percent have the strongest exfoliating action. Products in this range may help treat nail fungus and soften thick nails.

Urea is a major component of the urine of mammals. So it’s not surprising that some people wonder if the urea in cosmetic comes from urine.

In commercial cosmetics, urea is made synthetically in a lab. Synthetic urea is also commonly added to baked goods and wines to help with fermentation.

Lotions and creams often contain urea to help moisturize dry or flaking skin or to act as a chemical exfoliator.

Urea used in skin care products is made synthetically and doesn’t contain animal byproducts.

Urea cream is generally considered safe, but it can cause skin irritation or an allergic reaction.