Absorbent

Magnesium Hydroxide

Reviewed by Daisy · Last updated 18 Aug 2026

Magnesium hydroxide is an active ingredient in milk of magnesia

What Is Magnesium Hydroxide?

Magnesium hydroxide is an active ingredient in milk of magnesia. It has an absorbent properties for skin.

How widely it's used

0.2%
of skincare products contain this ingredient — placing it in the top 25% of most-used ingredients.
Most common in: Sunscreens

Regulatory information

Standardised cosmetic-ingredient identifiers used by regulators.

Show identifiers
INCI Name
MAGNESIUM HYDROXIDE
INN Name
magnesia
EC Number
215-170-3
Pharmacopoeia Name
magnesii hydroxidum
Function
Absorbent, Buffering

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