Propylene Glycol

A humectant that draws moisture into the skin and acts as a solvent. Propylene Glycol functions primarily as a humectant by drawing water from the environment and deeper epidermal layers into the stratum corneum, thereby enhancing skin hydration and maintaining barrier integrity. It also acts as a penetration enhancer by interacting with and disrupting the lipid matrix of the stratum corneum, which facilitates the transdermal delivery of other active ingredients. Furthermore, it serves as an excellent solvent, helping to solubilize active and inactive ingredients in a formulation, ensuring uniform distribution and stability.

The Cosmetic Ingredient Review (CIR) Expert Panel has assessed Propylene Glycol as safe for use in cosmetic formulations. While generally well-tolerated, it can cause mild skin irritation or allergic contact dermatitis in sensitive individuals, particularly at higher concentrations or in those with a compromised skin barrier.

Look for products with 1-20% (most formulas use 1-10% for humectant properties, but it can be used up to 50% in specialized solvent systems or topical drug formulations; higher concentrations may increase potential for irritation). for clinical efficacy.