Saccharide Isomerate

Saccharide isomerate is a carbohydrate-derived humectant (often used around 1–5%) designed to bind to skin keratin and improve hydration, and it is generally well-tolerated in clinical use with low rates of stinging compared with many actives. While true irritation is uncommon, in highly reactive or eczema-prone patients any leave-on ingredient can occasionally provoke burning/itch (especially on compromised barriers), so it is best classified as very gentle rather than completely inert. Safety Notes: In commercial skincare, saccharide isomerate is most often used as a leave-on humectant (frequently via the marketed blend Pentavitin) at low supporting levels around 0.1–0.3% in cleansers, toners, and emulsions where it is not the primary claim ingredient. Typical effective use levels in leave-on moisturizers/serums cluster around ~1–3%, while the highest OTC “intense hydration/72h” style serums and gel-creams reach about 5% (usually near the top practical limit for sensorial/stability and tack control). There are no specific FDA/EU cosmetic maximum limits for saccharide isomerate itself, so the observed range is driven mainly by performance, feel, and cost rather than regulation; rinse-off products generally sit toward the low end.