Magnesium Hydroxide


Magnesium Hydroxide suspension is used in constipation, heart burn, gas and nausea. It is also indicated in acute and long acting constipation due to hyper acidity and peptic ulcer or stomatitis.


Magnesium Hydroxide is popularly known as Milk of Magnesia. It is a mildly acting antacid and laxative. It is poorly and slowly absorbed and acts by its osmotic properties in the luminal fluid which causes retention of fluid in the bowel. It is useful for emptying the bowel prior to surgical, radiological and colonoscopic procedures and can help to eliminate parasites following appropriate therapy and toxic material in some cases of poisoning. Magnesium Hydroxide is converted into Magnesium Chloride in the stomach without forming carbon dioxide

Dosage & Administration

As Laxative:
  • Adults: 2-4 Tablespoonful with a full glass of water.
  • Children: 6-11 years: 1-2 Tablespoonful with a full glass of water. 2-5 years: 1-3 Teaspoonful with a full glass of water.
As Antacid:
  • Adults: 1-3 teaspoonful (5 to 15 ml) up to 4 times daily with water.
  • Children: 1-3 years: ¼ teaspoonful. 3-6 years: ¼-½ teaspoonful. 6-12 years: ½-1 teaspoonful


Magnesium hydroxide can decrease the absorption of other drugs such as, digoxin, mycophenolate, phosphate supplements (e.g., potassium phosphate), tetracycline antibiotics, certain azole antifungals (ketoconazole, itraconazole), and quinolone antibiotics (e.g., ciprofloxacin, levofloxacin).


Magnesium Hydroxide should not be administered where use of laxative is contraindicated. Long term treatment of Magnesium Hydroxide is contraindicated in patients with renal failure.

Side Effects

Magnesium Hydroxide in common with other magnesium salts may cause diarrhoea.

Precautions & Warnings

The drug should be avoided if possible in patients with renal and hepatic failure and in those with heart block and myocardial disease. The drug may be used cautiously in pregnancy.

Therapeutic Class

Antacid with laxative action

Storage Conditions

Store in a cool & dry place, protected from light. Keep all medicines out of reach of children.