Urea

Multifunctional NMF component with concentration-dependent action: ≤2% pure humectant, 5–10% moisturizer with mild keratolytic benefit, 10–30% keratolytic, 30–40% nail/callus debriding agent. Mechanistically unique within humectants: upregulates filaggrin expression (the strongest known upregulation among topical cosmetic actives) plus loricrin, transglutaminase-1, cathelicidin, and β-defensin-2 — reinforcing barrier function at a genetic transcription level beyond simple water attraction. An RCT confirmed 4% urea superior to 20% glycerin for TEWL reduction in atopic dermatitis. Natural NMF component (~7% of NMF) and can act as an endogenous humectant replacing water under low-humidity conditions. Vehicle is critical: W/O emulsions with occlusion outperform standalone aqueous. Maintain pH 4–8; avoid >pH 8 at elevated temperature to prevent ammonia formation. The EU classifies Urea as "permitted". Safety rating: GOOD. 10 toxicological study endpoint(s) are available in our database.

Urea EU regulatory status: permitted. Maximum allowed concentration: No concentration restriction for cosmetic use; ≥10% exerts keratolytic activity — label accordingly; ≥30% debriding use requires appropriate regulatory framing. This is based on EU Regulation 1223/2009 and its amendments.

Urea functions as: Humectant (≤2%), moisturizer/mild keratolytic (5–10%), keratolytic (10–30%), debriding agent (30–40%), filaggrin upregulator, antimicrobial peptide inducer. It is classified as a Humectant in our database. CAS number: 57-13-6.

adequate The Margin of Safety (MoS) is calculated using SCCS methodology. A MoS above 100 is generally considered safe. Use the MoS Calculator tool to calculate MoS for your specific formulation and product category.

The NOAEL (No Observed Adverse Effect Level) for Urea is 50000 mg/kg bw/day based on a Developmental study via oral route in rat. A total of 10 study endpoints are available. Source: COSMOS_DB.