Milk of Magnesia taken as a laxative or antacid can increase magnesium intake:

Taking the recommended dose as a laxative (2 to 4 Tbsp.) provides 990 to 1950 mg magnesium.

Taking the recommended dose as an antacid (1 to 3 tsp.) provides 165 to 500 mg magnesium.

Medications that can cause high serum magnesium:

Lithium Carbonate

Listed below are medications that increase the urinary excretion of magnesium:


Drugs used in heart disease

Antiarrhythmic Drugs

Quinidine, Sotalol, Aamiodarone, Bretylium

Digoxin and Strophanthin

Adrenalin and drugs that mimic its activity, such as isoproterenol



Ethacrynic Acid


Osmotic Agents


Drugs to treat allergies




Antihistamines: astemizole, terfenadine


Drugs used in mental disorders


thioridazine, trifluoperazine





Amphotericin B

Aminoglycoside group of antibiotics




Other medications

Antineoplastic drugs and radiation




Hydrocortisone and other cortisone drugs

Antacids can affect absorption of other drugs, many contain magnesium




High dose calcium

High dose vitamin D

High Intake of caffeine (coffee, tea)



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