MedlinePlus Drug Information: Magnesium Hydroxide

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Other drug names:	A-Am An-Az B C-Ch Ci-Cz D-Dh Di-Dz E F G H I-J K-L M-Mh Mi-Mz N-Nh Ni-Nz O P-Pl Pm-Pz Q-R S-Sn So-Sz T-To Tp-Tz U-V W-Z 0-9

Magnesium Hydroxide

(mag nee' zhum hye drox' ide)

Brand name(s): Milk of Magnesia; Milk of Magnesia-Concentrated; Phillips Milk of Magnesia

Contents of this page:
Why is this medication prescribed? How should this medicine be used? What special precautions should I follow? What should I do if I forget a dose?	What side effects can this medication cause? What storage conditions are needed for this medicine? What other information should I know?

Why is this medication prescribed?

Magnesium hydroxide is used on a short-term basis to treat constipation.

This medication is sometimes prescribed for other uses; ask your doctor or pharmacist for more information.

How should this medicine be used?

Magnesium hydroxide come as a tablet and liquid to take by mouth. It usually is taken as needed for constipation. Follow the directions on the package or on your prescription label carefully, and ask your doctor or pharmacist to explain any part you do not understand. Take magnesium hydroxide exactly as directed. Do not take more or less of it or take it more often than prescribed by your doctor.

Shake the liquid well before each use.

What special precautions should I follow?

Before taking magnesium hydroxide,

tell your doctor and pharmacist if you are allergic to magnesium hydroxide or any other drugs.
tell your doctor and pharmacist what prescription and nonprescription medications you are taking, including vitamins.
tell your doctor if you have or have ever had kidney disease.
tell your doctor if you are pregnant, plan to become pregnant, or are breast-feeding. If you become pregnant while taking magnesium hydroxide, call your doctor.

What should I do if I forget a dose?

This medication usually is taken as needed. If your doctor has told you to take magnesium hydroxide regularly, take the missed dose as soon as you remember it. However, if it is almost time for the next dose, skip the missed dose and continue your regular dosing schedule. Do not take a double dose to make up for a missed one.

What side effects can this medication cause?

Although side effects from magnesium hydroxide are not common, they can occur. If you experience any of the following symptoms, call your doctor immediately:

stomach cramps
upset stomach
vomiting
diarrhea

What storage conditions are needed for this medicine?

Keep this medication in the container it came in, tightly closed, and out of reach of children. Store it at room temperature and away from excess heat and moisture (not in the bathroom). Throw away any medication that is outdated or no longer needed. Talk to your pharmacist about the proper disposal of your medication.

What other information should I know?

Ask your pharmacist any questions you have about taking this medicine.

Last Revised - 01/01/2003

American Society of Health-System Pharmacists, Inc. Disclaimer