• You are here: Home > eXpert Advice > Health Notes

View Basket / Checkout

Magnesium Hydroxide

Also indexed as: Cream of Magnesia, Magnesium Hydroxide Mixture (BP), Milk of Magnesia, MOM

Illustration

Magnesium hydroxide is used as an antacid for short-term relief of stomach upset and as a laxative for short-term treatment of constipation. Magnesium hydroxide is available in nonprescription products alone and in combination with other nonprescription ingredients to relieve stomach upset.

Summary of Interactions with Vitamins, Herbs, and Foods
In some cases, a herb or supplement may appear in more than one category, which may seem contradictory. For clarification, read the full article for details about the summarized interactions.

Beneficial May Be Beneficial: Depletion or interference—The medication may deplete or interfere with the absorption or function of the nutrient. Taking these nutrients may help replenish them.

Folic Acid

Iron*
Check Check: Other—Before taking any of these supplements or eating any of these foods with your medication, read this article in full for details.

Potassium
Side effect reduction/prevention

None known
Supportive interaction

None known
Reduced drug absorption/bioavailability

None known
Adverse interaction

None known

An asterisk (*) next to an item in the summary indicates that the interaction is supported only by weak, fragmentary, and/or contradictory scientific evidence.

Interactions with Dietary Supplements

Folic acid
Folic acid is needed by the body to utilise vitamin B12. Antacids, including magnesium hydroxide, inhibit folic acid absorption.1 People taking antacids are advised to supplement with folic acid.

Iron
Antacids, including magnesium hydroxide, may reduce the absorption of dietary iron. Iron supplements do not require stomach acid for absorption and one human study found that a magnesium hydroxide/aluminium hydroxide antacid did not decrease supplemental iron absorption.2

Potassium
Individuals taking potassium-depleting diuretics and those who are otherwise at risk of developing potassium deficiency (such as people with chronic diarrhoea or vomiting) may experience a fall in serum potassium levels if they take magnesium without taking additional potassium.3 This could lead to muscle cramps or, in individuals taking digoxin or digitalis, more serious problems such as cardiac arrhythmias. Individuals who have a history of potassium deficiency and those who are at risk of developing potassium deficiency, as well as people taking digoxin or digitalis, should consult a physician before taking magnesium-containing products.

References

1. Russell RM, Golner BB, Krasinski SD, et al. Effect of antacid and H2 receptor antagonists on the intestinal absorption of folic acid. J Lab Clin Med 1988;112:458–63.

2. O’Neil-Cutting MA, Crosby WH. The effect of antacids on the absorption of simultaneously ingested iron. JAMA 1986;255:1468–70.

3. Dyckner T, Wester PO. Ventricular extrasystoles and intracellular electrolytes before and after potassium and magnesium infusions in patients on diuretic treatment. Am Heart J 1979;97:12–8.