milk of magnesia

chemical compound

Also known as: magnesia magma

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Last updated

June 30, 2026

Quick Summary

Milk of magnesia is a suspension of magnesium hydroxide in water. Magnesium hydroxide is a crystalline compound with the chemical formula Mg(OH)₂. It is slightly alkaline and is commonly used as an antacid to neutralize stomach acid and as a laxative. Magnesium itself is an alkaline-earth metal and is essential for all cellular life, playing a role in various biological processes and being a key component of chlorophyll in plants. While "magnesia" can refer to magnesium oxide, "milk of magnesia" specifically denotes the suspension of magnesium hydroxide.1234

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magnesium processing
Chemical compounds
The best-known medical compounds are milk of magnesia, or magnesium hydroxide, which is used as an antacid or as a mineral supplement to maintain the body’s magnesium balance. The hydrous magnesium sulfate popularly known as Epsom salts, MgSO₄·7H₂O, is used as a laxative.
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The best-known medical compounds are milk of magnesia, or magnesium hydroxide, which is used as an antacid or as a mineral supplement to maintain the body’s magnesium balance. The hydrous magnesium sulfate popularly known as Epsom salts, MgSO₄·7H₂O, is used as a laxative.
Read More