Diglucosyl Gallic Acid

Diglucosyl Gallic Acid is a water-soluble gallic-acid derivative used mainly as an antioxidant/brightening support ingredient, typically at low concentrations (~0.1–1%). Available safety and use data suggest low direct irritancy compared with free phenolic acids, but as a polyphenol derivative it can still provoke stinging or reactivity in a subset of highly sensitive or eczema-prone patients, especially in compromised barriers or multi-active routines. Given limited large-scale irritation benchmarking and the need to err toward patient safety, it fits best as a generally well-tolerated but not “post-procedure inert” ingredient. Safety Notes: In commercial skincare, diglucosyl gallic acid is typically used as a brightening/antioxidant active and often appears in leave-on serums and creams at low inclusion levels around 0.05–0.3% when part of multi-active formulas. Dedicated tone-correcting products and “booster” style formulations sold OTC are commonly formulated around ~0.5–2%, with the highest consumer-available products observed reaching about 3% (generally leave-on; rinse-off products tend to sit at the lower end due to short contact time). No specific global maximum concentration limit is widely codified for this ingredient in major cosmetic regulations, so the upper bound is primarily driven by stability, solubility, sensorial constraints, and irritation risk rather than an explicit regulatory cap.