Stable vitamin C derivative. Better pH stability than L-ascorbic acid; penetrates skin and converts to the active form. Antioxidant and brightening effect.
Topical application
AProven efficacy. Two or more independent RCTs with instrumental endpoints.
Modern stable vitamin C form with accumulated evidence base. Does not cause the irritation typical of pure L-ascorbic acid.
3-O-Ethyl ascorbic acid (EAA) is a stable etherified vitamin C derivative. The ethyl group protects the molecule from oxidation, making it resistant to light, oxygen, and temperature, unlike pure L-ascorbic acid. After topical application skin esterase enzymes cleave the ethyl group, releasing active ascorbate. Mechanism. Antioxidant, tyrosinase inhibitor, cofactor for prolyl hydroxylase in collagen synthesis. Stable across a broad pH range (4-7) – EAA formulas sting less and oxidize less often. Where applied. Brightening and antioxidant serums and creams (2-10%). Brands include The Ordinary Ethylated Ascorbic Acid 15%, Paula's Choice C15, Spanish Mesoestetic AOX Ferulic. Evidence base. Stamford 2012 showed EAA penetrates the epidermis better than L-ascorbic acid at the same w/w due to greater lipophilicity. Ochiai 2006 in melasma patients: 2% EAA reduced pigmentation over 8 weeks more than placebo. Few head-to-head RCTs with 15% L-ascorbic acid exist; most data come from manufacturers. Safety. CIR/SCCS confirm safety. Less irritating than pure ascorbic acid (pH 6-7 vs 2.5-3.5). Suitable for sensitive skin and vitamin C beginners. Pregnancy and lactation – safe. Not in the restriction lists of SEGO 2023 or AEDV 2024. Suitable for. Hyperpigmentation, post-acne marks, gestational melasma, photoaging, sensitive skin intolerant to acidic L-ascorbic acid.
Irritation potential
LowAllergen risk
LowPregnancy
SafeSuitable for
Works well with
Hydroxypinacolone RetinoateГидроксипинаколон ретиноат
Granactive Retinoid (HPR) activates at neutral pH, so stable C forms pair well. With ethyl ascorbate, no irritation and no loss of activity for either molecule.
RetinolРетинол
Unlike L-ascorbic acid, ethyl ascorbate is stable at neutral pH, so it can sit in the same formula or routine as retinol. Alternation is optional: C in the morning with SPF and retinol at night is best, but a single product works too.
RetinaldehydeРетиналь
Retinal is sensitive to low pH, so L-AA does not pair with it. Ethyl ascorbate works at neutral pH and can be combined with retinal without loss of activity for either.
The Evigrade extension adds an evidence panel to Wildberries, Goldapple, Letu, iHerb, Sephora and 12 more stores. This ingredient and every other one in the product show evidence-tier, allergen risk and pregnancy/lactation flags at a glance.
3-O-Ethyl Ascorbic Acid is considered safe during pregnancy at typical cosmetic concentrations. Systemic absorption through the skin is minimal.
3-O-Ethyl Ascorbic Acid suits: normal, dry, oily, combination, sensitive.
Stable vitamin C derivative.
The INCI name is 3-O-Ethyl Ascorbic Acid. It may also appear as: Ethyl Ascorbic Acid, EAA.
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