Table of ContentsView AllTable of ContentsUsesSide EffectsPrecautionsDosageToxicityInteractionsSourcesFrequently Asked Questions
Table of ContentsView All
View All
Table of Contents
Uses
Side Effects
Precautions
Dosage
Toxicity
Interactions
Sources
Frequently Asked Questions
Magnesium oxideis a form ofmagnesiumsalt that is most commonly used to treat low magnesium levels and constipation. It has also been studied for its effects on blood pressure,type 2 diabetes, andmigraines.Most people get magnesium from food, but supplementation is sometimes needed.
Magnesium oxide is one of a few types of magnesium supplements you can get without a prescription. It is also an ingredient in some over-the-counter (OTC) medications. It’s generally safe but may cause stomach aches and diarrhea. The recommended daily magnesium intake from all sources is between 310 milligrams (mg) and 400 milligrams for younger adults and between 320 milligrams and 420 milligrams for older adults.
In the United States, the Food and Drug Administration (FDA) does not regulate supplements the way it regulates prescription drugs. That means some supplement products may not contain what the label says. Whenchoosing a supplement, look for independently tested products and consult a healthcare provider, registered dietitian nutritionist (RD or RDN), or pharmacist.
Viktoriya Skorikova / Getty Images
Uses of Magnesium Oxide
Magnesium oxide is a magnesium mineral supplement that has magnesium and oxygen ions.
Supplement FactsActive ingredient(s): Magnesium oxideAlternate name(s):MagnesiaLegal status:Available over-the-counter (OTC) in supplements and some laxativesSuggested dose: Between 310 milligrams and 420 milligrams in adults, based on ageSafety considerations: Generally safe, but may cause stomach aches and diarrhea
Supplement Facts
Active ingredient(s): Magnesium oxideAlternate name(s):MagnesiaLegal status:Available over-the-counter (OTC) in supplements and some laxativesSuggested dose: Between 310 milligrams and 420 milligrams in adults, based on ageSafety considerations: Generally safe, but may cause stomach aches and diarrhea
Magnesium Blood Test: What to Know
Magnesium Deficiency
Early signs of a magnesium deficiency include:
When the deficiency gets worse, symptoms can include:
You can get magnesium through your diet and supplements. Before starting any supplements, please discuss them with your healthcare provider.
6 Ways Magnesium Can Help You Reach Your Weight Loss Goals
Constipation
Magnesium is an ingredient in somelaxatives(e.g., Philips' Milk of Magnesium).The supplement draws water into the intestines to soften stool, making it easier to pass (osmotic effect).
One randomized, double-blind, placebo-controlled trial looked at the effects of magnesium oxide in adults with chronic mild-to-moderate constipation. Seventeen people took magnesium oxide for 28 days and 17 took a placebo.
At the end of the study, magnesium oxide significantly improved participants’ overall symptoms, including spontaneous bowel movement, stool form, colonic transit time, and abdominal symptoms compared to taking the placebo.
Magnesium oxide should only be used as a short-term treatment forconstipation.If you have constipation, talk to your healthcare provider about the best treatment for you. Call your provider if your constipation does not get better or gets worse after trying magnesium oxide.
Blood Pressure and Risk of Stroke
Magnesium oxide might help reducehigh blood pressure(hypertension) and lower the risk of stroke.
Another systematic review of 49 studies on oralmagnesium supplementation and blood pressureshowed promising but conflicting results:
Type 2 Diabetes
Diets high in magnesium have been associated with a lower risk of type 2 diabetes.
One long-term meta-analysis of seven studies including 286,668 people found that 100 milligrams per day in total magnesium intake significantly lowered the risk of diabetes.
Another meta-analysis of 13 studies demonstrated a dose-dependent association between magnesium intake and type 2 diabetes risk. However, this was only statistically significant in people who were overweight.
However, very few short-term clinical trials have been done on magnesium oxide’s effects on controlling type 2 diabetes.The American Diabetes Association (ADA) states there is not enough research to support using magnesium supplements to improve blood glucose in people with type 2 diabetes.
If you have diabetes, talk to your provider before starting magnesium oxide supplementation.
Migraines
Magnesium oxide supplementation may reduce the number and intensity ofmigraines.
A randomized, double-blind crossover study showed that taking 500 milligrams of magnesium oxide appeared to be as effective as valproate sodium in preventing migraine attacks. Sixty-three people in the study took either magnesium oxide or valproate sodium.
The American Academy of Neurology and the American Headache Society concluded that magnesium therapy is “probably effective” for migraine prevention, but research is limited.
It’s also important to note that the typical dose of magnesium used for migraine prevention is higher than magnesium’s tolerable upper limit (UL). Therefore, it should only be used under the supervision of a healthcare provider.
Please discuss the use of magnesium oxide supplements with your healthcare provider before taking them if you have migraines.
How It Compares to Other Forms of Magnesium
Other types of magnesium supplements include:
Bruce Gifford/Getty Images.
What Are the Side Effects of Magnesium Oxide?
Consuming a supplement like magnesium oxide may have side effects. These side effects may be mild or severe.
Upset stomach and diarrhea are the most common side effects of magnesium oxide.Taking magnesium oxide with food can often prevent these side effects. If side effects do not get better or are getting worse, it is best to talk to your healthcare provider.
Severe allergic reactions to magnesium oxide are rare. However, seek immediate medical help if you develop:
People with kidney problems should ask their providers before starting magnesium oxide supplements.In addition, pregnant and lactating people, as well as children, should avoid magnesium oxide supplements because the risks to these groups are unknown.
Dosage: How Much Magnesium Oxide Should I Take?
Always speak with a healthcare provider before taking a supplement to ensure that the supplement and dosage are appropriate for your needs.
The following is the Recommended Dietary Allowance (RDA) for magnesium:
Discuss your use of magnesium oxide with your provider to find out the safest and most effective amount to take for your needs.
What Happens If I Take Too Much Magnesium Oxide?
It ispossible to take too much magnesium oxide. Large doses of magnesium oxide can cause magnesium toxicity, but this is more likely in people with kidney problems.
Taking too much magnesium oxide may cause:
If you have any of these symptoms after taking magnesium oxide, seek medical care right away.
Magnesium oxide may prevent the absorption of several medications. Before starting magnesium oxide supplementation, please discuss the prescription and OTC medications, vitamins, or herbal supplements that you take with your healthcare provider.
Magnesium oxide might reduce how well the Parkinson’s disease treatment Sinemet (levodopa and carbidopa) works. However, more studies are needed.
Other medications that can interact with magnesium oxide include:
Magnesium oxide may interact with the following supplements:
Other interactions may occur. Before starting magnesium oxide, ask your healthcare provider or pharmacist for a complete list of potential drug, supplement, and food interactions.
Read the Product LabelCarefully read a supplement’s ingredient list and nutrition facts panel to know which ingredients and how much of each ingredient is included. Please review this supplement label with your healthcare provider to discuss any potential interactions with foods, other supplements, and medications.
Read the Product Label
Carefully read a supplement’s ingredient list and nutrition facts panel to know which ingredients and how much of each ingredient is included. Please review this supplement label with your healthcare provider to discuss any potential interactions with foods, other supplements, and medications.
Sources of Magnesium Oxide
Magnesium is found in many plant and animal foods and beverages, including green leafy vegetables (spinach), legumes, nuts, seeds, and whole grains. Usually, foods that are higher in fiber are rich in magnesium.
Magnesium oxide supplements are available OTC without a prescription. Magnesium oxide is sold under several brand names. Your healthcare provider or pharmacist can advise you on which brand might fit your unique situation and overall health.
Summary
Magnesium oxide is a type of magnesium. It’s often an ingredient in laxatives and supplements.
Getting enough magnesium is important for good health. Without it, the body cannot function properly. Eating magnesium-rich foods, like green leafy vegetables, legumes, nuts, seeds, and whole grains, is usually enough to get the magnesium you need.
It’s important to make sure you get enough magnesium without getting too much. You should always talk to your provider before starting any supplement. If you think you have low magnesium levels, ask your provider to check them.
How to Use Magnesium to Prevent Migraines
Frequently Asked QuestionsThe best way to get magnesium is through your diet and eating a variety of magnesium-rich foods, such as spinach, legumes, nuts, seeds, and whole grains.Supplements are an option for maintaining magnesium levels in people whose levels remain low despite diet changes. Please talk to your healthcare provider before starting a magnesium oxide supplement.A healthcare provider can assist you in determining if magnesium oxide supplements are needed for maintaining and/or increasing magnesium. A blood test is usually used to check the level of magnesium in your blood.Anyone who thinks their magnesium is low should talk to their healthcare provider before starting a supplement.
The best way to get magnesium is through your diet and eating a variety of magnesium-rich foods, such as spinach, legumes, nuts, seeds, and whole grains.Supplements are an option for maintaining magnesium levels in people whose levels remain low despite diet changes. Please talk to your healthcare provider before starting a magnesium oxide supplement.
The best way to get magnesium is through your diet and eating a variety of magnesium-rich foods, such as spinach, legumes, nuts, seeds, and whole grains.
Supplements are an option for maintaining magnesium levels in people whose levels remain low despite diet changes. Please talk to your healthcare provider before starting a magnesium oxide supplement.
A healthcare provider can assist you in determining if magnesium oxide supplements are needed for maintaining and/or increasing magnesium. A blood test is usually used to check the level of magnesium in your blood.Anyone who thinks their magnesium is low should talk to their healthcare provider before starting a supplement.
A healthcare provider can assist you in determining if magnesium oxide supplements are needed for maintaining and/or increasing magnesium. A blood test is usually used to check the level of magnesium in your blood.
Anyone who thinks their magnesium is low should talk to their healthcare provider before starting a supplement.
22 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.
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