Magnesium Hydroxide

Synonyms: E528; Hydroxid hořečnatý; Magnesii hydroxidum; Magnesio, hidróxido de; Magnesium Hydrate; Magnésium, hydroxyde de; Magnesiumhydroksidi; Magnesiumhydroxid; Magnézium-hidroxid; Magnezyum Hidroksit; Magnio hidroksidas.
Cyrillic synonym: Магния Гидроксид.

💊 Chemical information

Chemical formula: Mg(OH)2 = 58.32.
CAS — 1309-42-8.
ATC — A02AA04; G04BX01.
ATC Vet — QA02AA04; QG04BX01.


In Eur., Int., US, and Viet.

Ph. Eur. 6.2

(Magnesium Hydroxide). A fine white or almost white amorphous powder. Practically insoluble in water; dissolves in dilute acids. A solution in water is alkaline to phenolphthalein.

USP 31

(Magnesium Hydroxide). A bulky white powder. Practically insoluble in water, in alcohol, in chloroform, and in ether; soluble in dilute acids. Store in airtight containers.

💊 Adverse Effects, Treatment, and Precautions

Interactions can be minimised by giving the antacid and any other medications 2 to 3 hours apart.

💊 Pharmacokinetics

Magnesium hydroxide, given orally, reacts relatively rapidly with hydrochloric acid in the stomach to form magnesium chloride and water. About 30% of the magnesium ions are absorbed from the small intestine, as described for Magnesium Salts.

💊 Uses and Administration

Magnesium hydroxide is an antacid that is given in oral doses of up to about 1 g. It is often given with aluminium-containing antacids such as aluminium hydroxide which counteract its laxative effect. Magnesium hydroxide is also given as an osmotic laxative in oral doses of about 2 to 5 g. Magnesium hydroxide has also been used as a food additive and as a magnesium supplement in deficiency states.

💊 Preparations

BP 2008: Co-magaldrox Oral Suspension; Co-magaldrox Tablets; Liquid Paraffin and Magnesium Hydroxide Oral Emulsion; Magnesium Hydroxide Mixture; USP 31: Alumina and Magnesia Oral Suspension; Alumina and Magnesia Tablets; Alumina, Magnesia, and Calcium Carbonate Oral Suspension; Alumina, Magnesia, and Calcium Carbonate Tablets; Alumina, Magnesia, and Simethicone Oral Suspension; Alumina, Magnesia, and Simethicone Tablets; Alumina, Magnesia, Calcium Carbonate, and Simethicone Tablets; Aspirin, Alumina, and Magnesia Tablets; Calcium Carbonate and Magnesia Tablets; Calcium Carbonate, Magnesia, and Simethicone Tablets; Magnesia Tablets; Magnesium Hydroxide Paste; Milk of Magnesia.

Proprietary Preparations

Arg.: Leche de Magnesia Phillips; Magnesia San Pellegrino; Braz.: Leite de Magnesia de Phillips; Leite de Magnesia†; Magnesiol†; Mylanta Plus; Canad.: Milk of Magnesia; Phillips’ Magnesia Tablets; Phillips’ Milk of Magnesia; Chile: Leche de Magnesia Phillips; Magnesia Pasteur; Tabletas Antiacidas; Denm.: Magnesia; Fin.: Emgesan; Magnesiamaito; Fr.: Carbonex; Magnesie S Pellegrino†; Gr.: Milk of Magnesia; Hung.: Antagel M; India: Tricaine-MPS; Indon.: Laxasium; Irl.: Milk of Magnesia; Israel: Magnesia S Pellegrino; Milk of Magnesia; Ital.: Citrato Espresso S. Pellegrino; Magnesia S Pellegrino; Magnesia Volta†; Mex.: Leche de Magnesia Normex; Port.: Leite Magnesia Phillips; Magnesia San Pellegrino; S.Afr.: Babys own Tummy Tablets; Deopens†; Spain: Magnesia; Magnesia San Pellegrino; Swed.: Emgesan; Switz.: Magnesia S Pellegrino; Thai.: Milk of Magnesia; Turk.: Magcine; Magnesie Calcinee; Magnesium Naneli Lafar; Magnokal; UK: Milk of Magnesia; USA: Dulcolax; Milk of Magnesia; Pedia-Lax; Phillips’ Chewable; Phillips’ Milk of Magnesia; Venez.: Magnesia San Pellegrino. Used as an adjunct in: Canad.: C2 with Codeine†; Denm.: Kodamid; Kodimagnyl; Magnyl; Gr.: Ascriptin†; Indon.: Naspro; Rheumapill; Israel: Ascriptin†; Ital.: Ascriptin; Aspirina 03; Mex.: Ascriptin; USA: Arthritis Pain Formula; Ascriptin; Asprimox; Cope; Magnaprin†; Vanquish; Venez.: Ascriptin.
Published January 27, 2019.