Lactic acid is an alpha-hydroxy acid (AHA) that exfoliates by loosening bonds between surface skin cells, promoting cell turnover, and also acts as a humectant to improve hydration. It is used to smooth texture, brighten tone, and improve signs of photoaging.
| Reported effect | How often | Notes |
|---|---|---|
Stinging or burning on application | Common | Transient sensation, especially at higher concentrations or low pH. |
Mild redness or erythema | Common | Usually temporary and resolves shortly after use. |
Skin dryness or peeling | Common | Result of increased exfoliation, more likely with frequent use. |
Increased photosensitivity | Common | AHAs raise sun sensitivity; daily sunscreen is recommended. |
Irritation or contact dermatitis | Uncommon | More likely in sensitive skin or at higher concentrations. |
Post-inflammatory hyperpigmentation | Rare | Mainly in darker skin tones following irritation or improper use. |
Chemical burn | Very rare | Associated with very high concentrations or prolonged contact, typically in peel settings. |
Frequencies reflect typical cosmetic use reported in the literature, not a guarantee for your skin.