Alpha-Arbutin

Alpha-arbutin is a tyrosinase-inhibiting brightening agent typically used around 1–2% in leave-on products and is generally well tolerated in clinical and consumer use. Irritation and stinging can occur, especially on compromised barriers or when layered with exfoliating acids/retinoids, but it is not considered a strongly irritating active at standard concentrations. Given the small but real risk in highly reactive/eczema-prone skin, it fits best as a gentle ingredient rather than “very gentle.” Safety Notes: In consumer skincare, alpha-arbutin is most often found in leave-on brightening serums/creams, with low-end usage around 0.1–0.5% in multi-ingredient tone-evening products where it is a supporting active. The most common “hero” serum strength on the mass and prestige market is 2%, while a smaller number of high-strength OTC specialty formulations are sold at 3% (typically anhydrous or tightly pH-controlled water-based systems to manage stability and discoloration risk). Rinse-off products (cleansers/soaps) tend to sit at the lower end due to short contact time and limited justification for higher dosing.