Top of the page
Pronunciation: mag-NEE-zee-um hi-DROX-ide
Common Brand Name(s): Milk Of Mag
This is a summary and does NOT have all possible information about this product. This information does not assure that this product is safe, effective, or appropriate for you. This information is not individual medical advice and does not substitute for the advice of your health care professional. Always ask your health care professional for complete information about this product and your specific health needs.
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.
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 persistent diarrhea, dehydration, and mineral imbalances (e.g., high magnesium).
Tell your doctor if your condition persists or worsens. 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, seek immediate medical attention.
Diarrhea may occur. If this effect persists or worsens, tell your doctor or pharmacist promptly.
If your doctor has directed you to use this medication, remember that your doctor has judged that the benefit to you is greater than the risk of side effects. Many people using this medication do not have serious side effects.
Tell your doctor right away if any of these unlikely but serious side effects occur:
A very serious allergic reaction to this drug is rare. However, seek immediate medical attention if you notice any symptoms of a serious allergic reaction, including:
This is not a complete list of possible side effects. If you notice other effects not listed above, contact your doctor or pharmacist.
In the US -
Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088 or at www.fda.gov/medwatch.
In Canada - Call your doctor for medical advice about side effects. You may report side effects to Health Canada at 1-866-234-2345.
Before taking magnesium hydroxide, tell your doctor or pharmacist if you are allergic to it; or if you have any other allergies. This product may contain inactive ingredients, which can cause allergic reactions or other problems. Talk to your pharmacist for more details.
Before using this medication, tell your doctor or pharmacist your medical history, especially of:
During pregnancy, this medication should be used only when clearly needed. Discuss the risks and benefits with your doctor.
It is not known whether this drug passes into breast milk. Consult your doctor before breast-feeding.
Drug interactions may change how your medications work or increase your risk for serious side effects. This document does not contain all possible drug interactions. Keep a list of all the products you use (including prescription/nonprescription drugs and herbal products) and share it with your doctor and pharmacist. Do not start, stop, or change the dosage of any medicines without your doctor's approval.
Some products that may interact with this drug include:
Magnesium hydroxide can decrease the absorption of other drugs such as dasatinib, delavirdine, atazanavir, gabapentin, digoxin, mycophenolate, phosphate supplements (e.g., potassium phosphate), tetracycline antibiotics (e.g., doxycycline, minocycline), certain azole antifungals (ketoconazole, itraconazole), and quinolone antibiotics (e.g., ciprofloxacin, levofloxacin). Separate your doses of these medications as far as possible from your doses of magnesium hydroxide. Ask your doctor or pharmacist about how long you should wait between doses and for help finding a dosing schedule that will work with all your medications.
If someone has overdosed and has serious symptoms such as passing out or trouble breathing, call 911. Otherwise, call a poison control center right away. US residents can call their local poison control center at 1-800-222-1222. Alberta residents can call PADIS (Poison and Drug Information Service) 24 hours a day at 1-800-332-1414. Canada residents can call a provincial poison control center. Symptoms of overdose may include: severe/persistent diarrhea, muscle weakness, mental/mood changes (e.g., confusion), slow/irregular heartbeat, decreased urination, dizziness.
Keep all regular medical and laboratory appointments.
Lifestyle changes such as regular exercise and diet changes (including drinking enough water, eating a proper diet with fiber-rich foods such as bran, fresh fruits/vegetables) may prevent or relieve constipation.
Lifestyle changes such as stress reduction programs, stopping smoking, limiting alcohol, and diet changes (e.g., avoiding caffeine/certain spices) may help to reduce heartburn and other stomach acid problems.
Talk to your doctor or pharmacist about lifestyle changes that might benefit you.
Store at room temperature away from light and moisture. If you have any questions about storage, ask your pharmacist. Do not store in the bathroom. Keep all medicines away from children and pets.
Do not flush medications down the toilet or pour them into a drain unless instructed to do so. Properly discard this product when it is expired or no longer needed. Consult your pharmacist or local waste disposal company for more details about how to safely discard your product.
Information last revised August 2021.
Copyright(c) 2021 First Databank, Inc.
Conditions of use: The information in this database is intended to supplement, not substitute for the expertise and judgment of healthcare professionals. The information in not intend to cover all possible uses, directions, precautions, drug interactions or adverse effects nor should it be construed in indicate that use of a particular drug is safe, appropriate or effective for you or anyone else. A healthcare professional should be consulted before taking any drug, changing any diet or commencing or discontinuing any course of treatment.
Healthwise, Healthwise for every health decision, and the Healthwise logo are trademarks of Healthwise, Incorporated.