Dextran

Dextran is a high–molecular weight polysaccharide used mainly as a humectant/texture agent in low concentrations (often ~0.1–5%) and is generally well tolerated on skin. Clinical and patch-test experience suggests it has low inherent irritancy, but in highly reactive or barrier-impaired patients occasional stinging or rare hypersensitivity has been reported with dextran-containing products, so I do not score it as inert. Given the mandate to protect severely sensitive users, it fits best as a very gentle ingredient rather than completely non-irritating. Safety Notes: In commercial skincare, dextran is most often used at very low levels (~0.01–0.1%) as a supportive polymer/humectant or as part of complex soothing/anti-redness blends in leave-on serums and eye products. Mid-range usage (~0.2–1%) appears in hydrating gels/creams where it contributes to skin feel and water-binding. The highest consumer-available levels observed are in specialized leave-on gel/serum textures and some hydrogel-type products where dextran functions as a primary film-former/thickener or biofunctional polysaccharide, reaching about 3–5%; rinse-off products typically sit at the lower end due to cost/benefit and sensorial considerations.