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Humectants & Emollients

Urea

Also known as: Carbamide, Urea cream

The skin's own moisturizer — a humectant at 10%, a keratolytic that dissolves rough callused skin at 20–40%.

  • By IngredientWiki Editorial Team
  • Fact-checked by IngredientWiki Editorial Team
  • Updated 2026-09-26
  • 2 min read

In short

Urea is a natural component of the skin's moisturizing factor and a workhorse in dermatology. At low concentrations (10% or less) it is a powerful humectant that draws water into the stratum corneum; at 20–40% it becomes a keratolytic — dissolving the keratin bonds of calluses, cracked heels, and thickened, scaly skin. It is a first-line treatment for dry skin conditions like xerosis, keratosis pilaris, and foot calluses, with decades of clinical use.

  • A natural part of the skin's own moisturizing system
  • 10% or less: hydrating humectant
  • 20–40%: keratolytic — softens calluses and scales
  • First-line for dry, rough, cracked skin

What is Urea?

Urea sounds industrial, but it is one of the most skin-native ingredients in dermatology — a natural component of the natural moisturizing factor that keeps the stratum corneum hydrated. Cosmetic chemists exploit a concentration-dependent magic trick: at 5–10%, urea is a superb humectant; at 20–40%, it denatures keratin's structure just enough to loosen dead, hardened skin. That dual personality makes urea the rare ingredient that treats both 'too dry' and 'too thick.'

Where it comes from

Natural sources

  • Produced endogenously in skin as part of the natural moisturizing factor
  • Found in sweat (trace amounts)
  • Industrially synthesized from ammonia and carbon dioxide

How it's made

Cosmetic and pharmaceutical urea is produced synthetically at high purity.

What it does in products

  • Humectant: binds water in the stratum corneum
  • Keratolytic at high strength: softens and sheds dead skin
  • Barrier repair support
  • Penetration enhancer for other actives

Benefits

Dry, rough skin (xerosis)

strong evidence

Urea creams at 10% are first-line treatments for xerosis, improving hydration and roughness within days to weeks — an established dermatology standard.

Cracked heels and calluses

strong evidence

At 20–40%, urea dissolves hardened keratin, visibly softening cracked heels and calluses — among the most reliable OTC treatments for foot skin.

Keratosis pilaris and scaling conditions

strong evidence

Urea smooths the rough bumps of keratosis pilaris and the scales of ichthyosis and psoriasis, often combined with other keratolytics.

Eczema adjunct

moderate evidence

Urea-containing emollients reduce dryness and may reduce flare frequency in atopic dermatitis when layered into standard care.

Side effects & safety

Stinging on cracked or inflamed skin (common)High-strength formulas sting on fissures; start with lower concentrations.
Irritation at 40% concentrations (uncommon)Reserve high strengths for thick skin (feet); avoid on the face.

Safety considerations

  • Topical urea is considered safe in pregnancy at standard concentrations.
  • None significant; urea can increase penetration of other actives.
  • Not for: Open wounds (stinging)
  • Not for: Known allergy (rare)

How it's used

In skincare

Facial and body lotions: 5–10% for daily hydration. Feet and elbows: 20% for maintenance, 40% for heavy calluses and cracked heels, applied once or twice daily. Apply to slightly damp skin for best humectant effect.

Regulatory status

  • Urea is an FDA OTC monograph ingredient as a skin protectant and keratolytic drug in higher concentrations; cosmetic uses fall under the FD&C Act.
  • INCI name on cosmetic labels: Urea.
  • The CIR Expert Panel has assessed urea as safe in cosmetics within concentration guidelines.

Popular products containing Urea

  • Urea 40% Foot CreamPurSources · Skincare
  • Rough & Bumpy Skin Cream (with urea)Gold Bond · Skincare
  • Urea 10% Body Lotion — Daily hydrating optionEucerin · Skincare

Product names and brands are shown for reference and belong to their respective owners.

The concentration guide

Urea's behavior flips at roughly 10%: below it, a gentle humectant suitable for face and body; at 10–20%, visible smoothing for rough patches; at 20–40%, true keratolysis for calluses and cracked heels. Choosing wrong is the most common urea mistake — 40% cream on facial skin stings badly, while 5% lotion on cracked heels does little. Match the percentage to the skin thickness.

Frequently asked questions

Can I use urea cream on my face?

Yes, at low concentrations (5–10%) — urea is a fine facial humectant. Avoid high-strength (20%+) products on the face; they are formulated for thick body skin.

Does urea burn?

High-strength formulas sting on broken or fissured skin for the first applications, which fades as the barrier heals. Persistent burning suggests the concentration is too high for the area.

How long does urea take to soften cracked heels?

Noticeable softening usually appears within 1–2 weeks of daily 20–40% application; significant improvement takes 3–4 weeks. Occlusion (cotton socks after application) speeds results.

The bottom line

Urea is dermatology's dry-skin specialist: 10% for hydration, 40% for demolishing calluses. Match the concentration to the body part, apply to damp skin, and cracked heels will meet their match within weeks.

References

  1. Urea in dermatology — literature search. PubMed (National Library of Medicine). https://pubmed.ncbi.nlm.nih.gov/?term=urea+keratolytic+xerosis
  2. Urea and skin hydration (review). PubMed (National Library of Medicine). https://pubmed.ncbi.nlm.nih.gov/?term=urea+stratum+corneum+hydration+review
  3. Urea compound summary. PubChem (National Library of Medicine). https://pubchem.ncbi.nlm.nih.gov/compound/1176
  4. Cosmetic Ingredient Review — urea safety assessment. Cosmetic Ingredient Review. https://www.cir-safety.org/ingredients