Ascorbic acid (vitamin C) at 23% is a high-concentration topical antioxidant that neutralizes free radicals, supports collagen synthesis, and helps reduce hyperpigmentation and uneven skin tone. At such elevated concentrations it can be more potent but also more irritating and prone to oxidation.
| Reported effect | How often | Notes |
|---|---|---|
Transient stinging or tingling | Common | Often occurs on application, especially at high concentrations and low pH. |
Skin redness or erythema | Common | More likely on sensitive or compromised skin barriers. |
Dryness or mild peeling | Uncommon | May result from low formulation pH and repeated use. |
Contact dermatitis | Rare | Allergic or irritant reactions reported in susceptible individuals. |
Yellowing of skin or product oxidation staining | Rare | Linked to oxidized ascorbic acid; cosmetic rather than harmful. |
Paradoxical hyperpigmentation | Very rare | Isolated reports, generally with irritation-induced post-inflammatory changes. |
Frequencies reflect typical cosmetic use reported in the literature, not a guarantee for your skin.