This is not a pure vitamin C serum. The active is 3-O-ethyl ascorbic acid, a vitamin C derivative, not L-ascorbic acid. Derivatives must convert to active vitamin C in the skin, and the evidence that they do so usefully is weaker than for the pure form. The 10% Vitamin C name reads like the pure serums, but the molecule is different.
The upside is comfort. This derivative is stable and does not need the low, stinging pH that L-ascorbic acid requires. Paired with colloidal oatmeal, licorice root, green tea and feverfew, the whole formula is built around not provoking the skin.
Of the common derivatives, 3-O-ethyl ascorbic acid is one of the better-studied — faint praise, but honest. For skin that cannot tolerate the real thing, that trade can be worth it; just do not expect the strength of pure vitamin C.
| Key active | 3-O-ethyl ascorbic acid 10% |
| Texture | Lightweight, silky serum |
| Best for | Sensitive, reactive, rosacea-prone skin |
| Approximate price | $48–$50 |
| Fragrance | Fragrance free |
For skin that cannot tolerate real vitamin C, this is a sensible option.
3-O-ethyl ascorbic acid is stable and does not need the low, stinging pH that L-ascorbic acid requires. Pair it with colloidal oatmeal, licorice root, green tea, and feverfew — all soothing — and you have a vitamin C that reactive skin can generally handle.
It is fragrance-free, and the whole formula is built around not provoking anything.
Of the common derivatives, 3-O-ethyl is one of the better-studied. That is faint praise, but it is honest praise.
It is not pure vitamin C, and the name does not say so. "10% Vitamin C" reads exactly like the CeraVe or L'Oréal products that contain the real thing. It does not.
The evidence is thinner. Derivatives must convert in the skin, and the data that they do so usefully is much weaker than for L-ascorbic acid.
$50 is a lot for a derivative — CeraVe's 10% pure L-ascorbic acid costs half that. You are paying for gentleness, and that is a legitimate thing to pay for, but be clear that is the trade.
Some users see very little brightening, which is the expected outcome of a genuinely mild formula.
Water, 3-O-Ethyl Ascorbic Acid, Squalane, Sodium Citrate, Tocopheryl Acetate, Colloidal Oatmeal, Chrysanthemum Parthenium Extract, Camellia Sinensis Leaf Extract, Glycyrrhiza Glabra Root Extract, Glycerin, Polyglyceryl-6 Polyricinoleate, Xanthan Gum, Polyglyceryl-10 Dioleate, Phenoxyethanol, Citric Acid, Sodium Benzoate, Potassium Sorbate, Sodium Hydroxide, Tetrasodium EDTA
1. The anti-melanogenic effects of 3-O-ethyl ascorbic acid via Nrf2-mediated α-MSH inhibition in UVA-irradiated keratinocytes and autophagy induction in melanocytes (https://doi.org/10.1016/j.freeradbiomed.2021.07.030) — Demonstrates that 3-O-ethyl ascorbic acid inhibits tyrosinase and acts as an effective skin-whitening/brightening agent, supporting the serum's brightening mechanism. 2. Lipid-Based Gels for Delivery of 3-O-Ethyl L-Ascorbic acid in Topical Applications (https://doi.org/10.3390/pharmaceutics16091187) — Shows 10% 3-O-ethyl L-ascorbic acid can be formulated into topical gels while retaining vitamin C antioxidant activity, backing the 10% concentration and its use in gentle formulations. 3. Vitamins and the skin: Vitamin C in dermatology (https://doi.org/10.1016/j.clindermatol.2026.02.007) — Confirms that L-ascorbic acid is intrinsically unstable and needs pH adjustment (low pH) formulation strategies, while derivatives are developed for enhanced stability, supporting the contrast the page draws. 4. A review of topical vitamin C derivatives and their efficacy (https://doi.org/10.1111/jocd.14465) — Reviews vitamin C derivatives developed to increase stability and skin absorption over L-ascorbic acid, supporting that ethyl ascorbic acid is a more stable derivative. 5. The Anti-Inflammatory Action of Cannabigerol Accompanied by the Antioxidant Effect of 3-O-ethyl Ascorbic Acid in UVA-Irradiated Human Keratinocytes (https://doi.org/10.1124/jpet.123.001731) — Documents antioxidant activity of 3-O-ethyl ascorbic acid in human skin keratinocytes, supporting that it is a relatively well-studied vitamin C derivative. 6. Colloidal Oatmeal (Avena Sativa) Improves Skin Barrier Through Multi-Therapy Activity (https://europepmc.org/article/MED/27272074) — Randomized clinical study showing colloidal oatmeal soothes and strengthens the skin barrier, supporting its inclusion as a soothing ingredient.