Water within the stratum corneum

Water within the stratum corneum refers to the intracellular and extracellular water located in the outermost layer of the epidermis. This water is critical for normal skin barrier function, maintaining flexibility, elasticity, and integrity of the skin. Its content is regulated by the balance between absorption (from underlying layers, environment, or topical agents) and loss to the environment via transepidermal water loss. The hydration state of the stratum corneum is mainly determined by corneocyte-bound water (influenced by keratin and natural moisturizing factors) and the organization of the extracellular lipid matrix, which controls water permeability[1][3][5][7]. Disruption of this balance can result in dry or compromised skin, leading to clinical issues such as eczema and increased susceptibility to irritation or infection[4]. The water content of the stratum corneum is not a discrete druggable target; rather, it is a measurable attribute and therapeutic endpoint for interventions that seek to restore or maintain skin hydration and barrier integrity[4][7].

Other names

Stratum corneum water contentstratum corneum hydrationskin surface water

Humectants: Attract and retain water within the corneocytes and extracellular matrix[4]. Occlusives: Form a hydrophobic barrier that reduces trans-epidermal water loss[4].