Magnesium Hydroxide

Pronounced

"mag-NEE-zee-um hi-DROX-ide"

Common brand names:

Milk Of Mag

Uses

This medication is used for a short time to treat occasional constipation. It is a laxative (osmotic-type) that is thought to work by drawing water into the intestines, an effect that helps to cause movement of the intestines.

This medication is also used to treat symptoms caused by too much stomach acid such as heartburn, upset stomach, or indigestion. It is an antacid that works by lowering the amount of acid in the stomach.

How to Use This Medication

Take this product by mouth as directed. For the chewable form, chew thoroughly before swallowing. For the liquid form, shake the bottle well before each dose. Carefully measure the dose using a special measuring device/spoon. Do not use a household spoon because you may not get the correct dose. If you are taking this medication for constipation, drink a full glass of water (8 ounces or 240 milliliters) with each dose. Follow all directions on the product package, or use as directed by your doctor. If you have any questions, ask your doctor or pharmacist.

Dosage is based on your medical condition and response to treatment.

Extended use or overuse of this medication for constipation may result in dependence on laxatives and ongoing constipation. Overuse may also cause diarrhea that doesn't stop, dehydration, and mineral imbalances (such as high magnesium).

Tell your doctor if your condition lasts or gets worse. For constipation problems, it may take 30 minutes to 6 hours to produce a bowel movement. Tell your doctor if this product does not produce a bowel movement, if you need to use this medication or other laxative products regularly for more than 1 week, or if you have rectal bleeding. For stomach acid problems, do not take the maximum dose of this medication for more than 2 weeks unless directed by your doctor. If you think you may have a serious medical problem, get medical help right away.

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Drug information is selected from data included with permission and copyrighted by First DataBank, Inc. This is a summary and does not contain all possible information about this product. For complete information about this product or your specific health needs, ask your healthcare professional. Always seek the advice of your healthcare professional if you have any questions about this product or your medical condition. This information is not intended as individual medical advice and does not substitute for the knowledge and judgment of your healthcare professional. This information does not contain any assurances that this product is safe, effective or appropriate for you.

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Information expires December 2025.