Hesperidin

Hesperidin is a citrus-derived flavonoid antioxidant/vasoprotective used at low levels in topical formulas (commonly ~0.1–2%) and is generally well-tolerated in clinical use with low rates of irritation in patch testing compared with acids, retinoids, or fragrance components. While sensitization is uncommon, botanical origin and potential impurities mean reactive eczema patients can still flare, so I score it as very gentle rather than exceptionally gentle. Safety Notes: In commercial skincare, hesperidin (typically as hesperidin or hesperidin methyl chalcone) is most often used in leave-on eye/anti-redness and “circulation” formulas at very low levels around 0.001–0.1% due to solubility and color/stability constraints. The highest OTC consumer-available products observed (targeted vascular/dark-circle/anti-bruising creams and specialty serums) reach about 1–2% total hesperidin-type flavonoid, generally in leave-on systems using solubilizers/encapsulation; rinse-off products are uncommon and usually sit at the low end because contact time is short.