Sodium hydroxide (NaOH), or lye, is a strong alkaline compound used in small amounts to neutralize and adjust the pH of cosmetic formulations. It is also used in saponification to produce soap and to buffer acidic actives to skin-tolerable levels.
| Reported effect | How often | Notes |
|---|---|---|
Skin irritation | Uncommon | More likely in poorly buffered or high-concentration formulas; finished products typically contain trace, neutralized amounts |
Chemical burns | Rare | Associated with concentrated raw material exposure, not properly formulated products |
Dryness or barrier disruption | Rare | Can occur if final product pH is too alkaline for skin |
Allergic contact dermatitis | Very rare | Reported only sporadically; primarily an irritant rather than a sensitizer |
Frequencies reflect typical cosmetic use reported in the literature, not a guarantee for your skin.