Sodium hydroxide (lye) is a strong alkaline compound used in small amounts to neutralize and adjust the pH of cosmetic formulations. It is not a treatment active but a formulation aid, often present at trace levels in finished products.
| Reported effect | How often | Notes |
|---|---|---|
Skin irritation | Uncommon | More likely with high concentrations or improperly balanced formulations; finished products are typically pH-neutralized. |
Chemical burns | Rare | Associated with concentrated solutions or accidental high-strength exposure, not properly formulated cosmetics. |
Dryness or stinging | Uncommon | Can occur on sensitive or compromised skin if formulation pH is too high. |
Eye irritation | Rare | Direct contact with concentrated forms can cause serious eye injury. |
Frequencies reflect typical cosmetic use reported in the literature, not a guarantee for your skin.
Peer-reviewed papers on this ingredient, via PubMed.