Table of ContentsView AllTable of ContentsHow Does It Work?Other UsesWho Should Avoid It?Other OptionsSeeking Medical Care
Table of ContentsView All
View All
Table of Contents
How Does It Work?
Other Uses
Who Should Avoid It?
Other Options
Seeking Medical Care
Milk of Magnesia, also known as magnesium hydroxide, is a common over-the-counter remedy used as both a laxative for treating constipation and an antacid for heartburn.
While generally safe for adults and children within recommended doses, Milk of Magnesia’s use in children requires additional consideration as it may not be well-tolerated in some children.
This article will explain how Milk of Magnesia works, its uses, standard dosage, and side effects to keep in mind.
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Milk of Magnesia for Constipation: How Does It Work?
Magnesium hydroxide, the active ingredient in Milk of Magnesia, is in a class of medications called saline laxatives. It is an osmotic laxative, meaning that when ingested, it draws water into the intestines, softening stool consistency and stimulating bowel movements.
The increased water content in the colon facilitates a smoother passage of stool and aids in alleviating constipation discomfort. Its osmotic effect within the intestines helps promote regularity and eases bowel movements, providing relief from constipation.
Other Uses of Milk of Magnesia
Magnesium hydroxide is often combined with calcium carbonate or aluminum hydroxide in commercial products for a more comprehensive effect or to balance out its potential side effects, like its laxative properties.
Standard Milk of Magnesia Dosage
Dosage guidelines for constipation:
When magnesium hydroxide is used as an antacid, it is important to adhere to the maximum recommended daily dosage within a 24-hour period. Ensure proper shaking of the product before consumption and consider diluting it with water if preferred.
Dosage guidelines for use as an antacid:
Possible Side Effects
Magnesium hydroxide might lead to certain side effects. Inform your healthcare provider if you experience persistent or bothersome symptoms, such as:
Additionally, some severe side effects require immediate attention. If you notice blood in your stool or are unable to have a bowel movement for six hours after using magnesium hydroxide, discontinue its use and contact your healthcare provider promptly.
Should Anyone Avoid Milk of Magnesia?
Magnesium hydroxide may be contraindicated for some people. Before consuming Milk of Magnesia, consult your healthcare provider if you:
Seek medical advice if you notice a sudden change in bowel habits lasting more than 14 days. Additionally, if you’re taking prescription medication, consult a healthcare provider or pharmacist before use, as this product may interact with certain prescriptions.
Discontinue use and consult a healthcare provider if you experience rectal bleeding or fail to have a bowel movement after using this product, as these could indicate a serious condition.
Milk of Magnesia Not Working: Other Ways to Relieve Constipation
Occasionally, Milk of Magnesia might not provide the expected relief from constipation. If this happens, talk to your healthcare provider about alternative options that may work for you.
Other ways to relieve constipation include:
Talk to your healthcare provider about alternative over-the-counter laxatives or stool softeners, such as:
Consult with a healthcare provider before trying new remedies for personalized guidance and to ensure safe and effective solutions for constipation relief.
When to See a Healthcare Provider
If you’re experiencing any of the following, it’s crucial to reach out to your healthcare provider for further guidance:
Seeking guidance from your provider can provide reassurance and appropriate care. Don’t hesitate to reach out if you’re encountering these symptoms.
Summary
The mechanism of Milk of Magnesia involves its osmotic effect, drawing water into the intestines to soften stool consistency and facilitate bowel movements. It is also used as an antacid—often along with other agents—to neutralize excessive stomach acid to ease the discomfort of heartburn and indigestion.
Fortunately, Milk of Magnesia is generally considered safe when used in recommended dosages. Talk with your healthcare provider if you experience side effects, the medication is not working, or you are interested in alternative medication options.
8 SourcesVerywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read oureditorial processto learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.MedlinePlus.Magnesium hydroxide.de Geus A, Koppen IJN, Flint RB, Benninga MA, Tabbers MM.An update of pharmacological management in children with functional constipation.Pediatric Drugs. 2023;25(3):343-358. doi:10.1007/s40272-023-00563-0Medline Plus.Aluminum hydroxide and magnesium hydroxide.Garg V, Narang P, Taneja R.Antacids revisited: review on contemporary facts and relevance for self-management.Journal of Internation Medical Research.2022;50(3):030006052210864. doi:10.1177/03000605221086457National Institutes of Health.Milk of Magnesia.MedlinePlus.Constipation.Failtdoctor.org.Laxatives: OTC products for constipation.Medline Plus.Constipation - self-care.
8 Sources
Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read oureditorial processto learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.MedlinePlus.Magnesium hydroxide.de Geus A, Koppen IJN, Flint RB, Benninga MA, Tabbers MM.An update of pharmacological management in children with functional constipation.Pediatric Drugs. 2023;25(3):343-358. doi:10.1007/s40272-023-00563-0Medline Plus.Aluminum hydroxide and magnesium hydroxide.Garg V, Narang P, Taneja R.Antacids revisited: review on contemporary facts and relevance for self-management.Journal of Internation Medical Research.2022;50(3):030006052210864. doi:10.1177/03000605221086457National Institutes of Health.Milk of Magnesia.MedlinePlus.Constipation.Failtdoctor.org.Laxatives: OTC products for constipation.Medline Plus.Constipation - self-care.
Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read oureditorial processto learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.
MedlinePlus.Magnesium hydroxide.de Geus A, Koppen IJN, Flint RB, Benninga MA, Tabbers MM.An update of pharmacological management in children with functional constipation.Pediatric Drugs. 2023;25(3):343-358. doi:10.1007/s40272-023-00563-0Medline Plus.Aluminum hydroxide and magnesium hydroxide.Garg V, Narang P, Taneja R.Antacids revisited: review on contemporary facts and relevance for self-management.Journal of Internation Medical Research.2022;50(3):030006052210864. doi:10.1177/03000605221086457National Institutes of Health.Milk of Magnesia.MedlinePlus.Constipation.Failtdoctor.org.Laxatives: OTC products for constipation.Medline Plus.Constipation - self-care.
MedlinePlus.Magnesium hydroxide.
de Geus A, Koppen IJN, Flint RB, Benninga MA, Tabbers MM.An update of pharmacological management in children with functional constipation.Pediatric Drugs. 2023;25(3):343-358. doi:10.1007/s40272-023-00563-0
Medline Plus.Aluminum hydroxide and magnesium hydroxide.
Garg V, Narang P, Taneja R.Antacids revisited: review on contemporary facts and relevance for self-management.Journal of Internation Medical Research.2022;50(3):030006052210864. doi:10.1177/03000605221086457
National Institutes of Health.Milk of Magnesia.
MedlinePlus.Constipation.
Failtdoctor.org.Laxatives: OTC products for constipation.
Medline Plus.Constipation - self-care.
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