Sodium Hydroxide

Sodium Hydroxide is an inorganic strong base, also known as lye. Used at controlled levels to raise formulation pH, neutralize acids, saponify fats in soapmaking, and adjust viscosity; higher concentrations can be harsh on skin and hair.
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Ingredient Snapshot

Overview
Lye used in small amounts to balance pH or make soap.
Category
Cleansing
Type
pH Adjuster

Ingredient Ratings

Overall Rating

Fair

Comedogenic Risk

None

Skin Benefits

It balances product pH so formulas are comfortable and effective to use, and enables soap formation for thorough rinse-off cleansing.

Uses In Skincare & Cosmetics

It's used in bar soaps and liquid cleansers to create the cleansing base, and employed in shampoos and to neutralize certain exfoliating treatments during manufacturing.

Comedogenic Rating

This ingredient is not typically evaluated for comedogenicity, and no standardized rating is available.

Safety

At the low levels used to adjust pH in finished products, it's typically safe, but it can sting or irritate skin and eyes, especially on compromised or sensitive skin. Higher concentrations are strongly irritating and must not contact skin undiluted; proper final pH minimizes the risk.

Is Sodium Hydroxide a Good Ingredient?

It rates Fair: it's genuinely useful as a pH adjuster and in soapmaking, but it can be irritating or caustic if concentration or final product pH isn't tightly controlled. Its benefits are functional rather than directly skin-improving, so careful formulation is essential to keeping it safe.

Products with Sodium Hydroxide

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