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Magnesium Oxide Coupon - Magnesium Oxide 400mg tablet

magnesium oxide

Generic
Used for Nutritional Deficiency
Used for Nutritional Deficiency

Magnesium oxide is an antacid that's used to relieve symptoms of acid reflux, such as heartburn, indigestion, and upset stomach. Some other magnesium oxide products can also be used as a supplement for many other health problems, including low magnesium levels. Some side effects can include diarrhea, nausea, and stomach cramping. Magnesium oxide is available as a tablet that you take by mouth and is found over the counter.

Reviewed by:
reviewer
Robert Chad Hakim, PharmD, BCCCP
reviewer
Allison Gourley, PharmD
Last reviewed on June 29, 2023
BasicsSide effectsPros & consPharmacist tipsFAQsWarningsDosageCostAlternativesLatest newsImagesReferencesPricesMedicare
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What is Magnesium oxide?

What is Magnesium oxide used for?

How Magnesium oxide works

Magnesium oxide is an antacid. It neutralizes the acid in your stomach. This helps relieve heartburn, indigestion, and upset stomach.

Magnesium oxide can also be used as a dietary supplement for people who have low blood magnesium levels. Magnesium is important to your health. It helps your body systems, like your nerves, muscles, and heart, work well.

Are you looking for information on magnesium citrate (Citroma) or magnesium hydroxide (Milk of Magnesia) instead?

Drug Facts

Common BrandsNone available
Drug ClassAntacid
Controlled Substance ClassificationNot a controlled medication
Generic StatusLower-cost generic available
AvailabilityOver-the-counter

More on Magnesium oxide essentials

Health: Supplements and herbs: assorted magnesium rich foods textured background 801110034

Magnesium: Overview and Benefits

Written by Sarah Gupta, MD
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What are the side effects of Magnesium oxide?

The following side effects may get better over time as your body gets used to the medication. Let your healthcare provider know immediately if you continue to experience these symptoms or if they worsen over time.

Common Side Effects

  • Diarrhea
  • Nausea
  • Stomach cramping

Serious Side Effects

Contact your healthcare provider immediately if you experience any of the following.
  • Dehydration: dry mouth, not urinating as much, lightheadedness, dizziness
  • Magnesium toxicity: dizziness, flushed skin, low energy, difficulty breathing, muscle weakness, abnormal heartbeat

Source: DailyMed

The following side effects have also been reported

Side effects that you should report to your care team as soon as possible:

  • Allergic reactions—skin rash, itching, hives, swelling of the face, lips, tongue, or throat
  • High magnesium level—confusion, drowsiness, facial flushing, redness, sweating, muscle weakness, fast or irregular heartbeat, trouble breathing

Side effects that usually do not require medical attention (report to your care team if they continue or are bothersome):

pros-and-cons

Pros and cons of Magnesium oxide

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Pros

Available over the counter

Has many health uses, such as heartburn relief

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Cons

Interacts with many medications, including certain antibiotics and thyroid medications

Might cause diarrhea and other stomach-related side effects

pharmacist-tips

Pharmacist tips for Magnesium oxide

pharmacist

  • Magnesium is available in many different forms and dosage strengths. Read the package label carefully to make sure you have the correct form of magnesium that you need and confirm that you're taking the correct dose. If you have questions about your dose, ask your pharmacist or healthcare provider for guidance.

    • If you're taking magnesium oxide for acid reflux and your symptoms last for more than 2 weeks, stop taking it and contact your healthcare provider. There might be a more serious health problem going on that your provider should check out.

      • If you're using magnesium oxide as a supplement to boost up your magnesium levels, eating foods that are high in magnesium can also help restore your nutrient levels.

        • Stay hydrated as much as possible to avoid dehydration from possible diarrhea. During treatment, let your provider know if you get dehydrated (e.g., dry mouth, not urinating as much, lightheadedness, dizziness, headaches).

          faqs

          Frequently asked questions about Magnesium oxide

          What's the difference between magnesium oxide and magnesium citrate?
          Both magnesium oxide and magnesium citrate are magnesium products that are available over the counter. Magnesium oxide is a tablet that's typically used as an antacid for heartburn and indigestion. Magnesium citrate is a liquid that's commonly used for constipation. Each medication provides a different amount of magnesium because they differ in how well they're absorbed into your body. This can affect the chance of experiencing side effects from the magnesium product (e.g., diarrhea). Ask your provider or pharmacist if you're not sure which magnesium product best fits your needs.
          Does magnesium oxide cause diarrhea?
          Yes, it's possible for any magnesium supplement, including magnesium oxide, to cause diarrhea. If you experience diarrhea when you take magnesium oxide, make sure to stay hydrated to avoid dehydration.
          Does magnesium oxide help with constipation?
          Some providers consider using magnesium oxide to treat constipation. In fact, the clinical guidelines for long-term constipation say that magnesium oxide is a possible option to help with constipation when additional fiber isn't enough. If you're having constipation problems, it's best to ask your provider how much magnesium oxide you can safely take because taking too much can raise your magnesium levels too high, which can be dangerous.
          Does magnesium oxide help you sleep?
          Research isn't completely clear on whether or not magnesium oxide actually helps with sleep. A review of three trials found that people who took magnesium supplements had some improvement in sleep, but it wasn't a significant enough of a difference from those who weren't taking magnesium. If you're having trouble sleeping, it's best to see your provider. They'll ask you questions to see whether simply making lifestyle changes, like limiting caffeine or reducing screen time, can help over taking a supplement like magnesium oxide.
          Can I use magnesium oxide to help prevent migraines if I'm pregnant?
          Based on a small study, it's possible that magnesium oxide might be a safe and effective way to help prevent migraines during pregnancy. More research is needed in this area, so make sure to talk to your provider before using magnesium oxide about its risks and benefits. They can help make sure you need to take it and that it's safe for you.
          Is it safe to take magnesium oxide if I have kidney problems?
          If you have kidney problems, you might be at risk of side effects and magnesium toxicity if you take magnesium oxide. This is because when you have kidney problems, your body might not be able to get rid of magnesium as well. As a result, magnesium can build up in the blood and cause dangerous side effects, like dizziness, low energy, nausea vomiting, and muscle weakness. If you have kidney problems, ask your provider if magnesium oxide is safe for you to use.
          Can I use magnesium oxide only when I need it?
          It depends on what you're using magnesium oxide for. If you're using magnesium oxide as an antacid to relieve acid reflux, then you can use it as you need it (but no more than twice per day). However, magnesium oxide is typically taken every day to help with low magnesium levels. Ask your provider before using magnesium oxide to see how long and how often you need to take this product.
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          What are the risks and warnings for Magnesium oxide?

          Magnesium oxide can cause some serious health issues. This risk may be even higher for certain groups. If this worries you, talk to your doctor or pharmacist about other options.

          risk-warning

          Diarrhea

          A possible side effect of magnesium oxide is diarrhea. Since you can lose a lot of fluids from your body when you have diarrhea, you might be at risk of getting dehydrated. Contact your provider if you feel dehydrated or have signs of dehydration (e.g., dry mouth, not urinating as much, lightheadedness, dizziness, headache). If you experience diarrhea that's bothersome or if you get dehydrated, your provider can recommend ways to help manage these problems.

          risk-warning

          Magnesium toxicity

          • Risk factors: Kidney problems | Taking more magnesium than recommended

            Having kidney problems or taking too much magnesium oxide can cause your blood magnesium levels to be too high and lead to serious side effects. Early symptoms of high magnesium levels can include dizziness, flushed skin, nausea, vomiting, and having lower energy. Call your healthcare provider right away if you experience any of these symptoms. Sometimes high magnesium levels can become more serious and lead to difficulty breathing, muscle weakness, and abnormal heartbeat. If this happens, get emergency help right away.

            dosage

            Magnesium oxide dosage forms

            The average cost for 30 tablets of 400mg of Magnesium oxide is $3.17 with a free GoodRx coupon. This is 57% off the average retail price of $7.37.
            tablet
            Tablet
            DosageQuantityPrice as low asPrice per unit
            400mg30 tablets$3.17$0.11

            Typical dosing for Magnesium oxide

            • Magnesium oxide 400 mg tablets

              • Antacid: The typical dose is 1 tablet by mouth twice per day, or as directed by your provider.

              • Supplement: The typical dose is 1 to 2 tablets by mouth per day, or as directed by your provider.

            • Magnesium oxide 420 mg tablets

              • Supplement: The typical dose is 1 tablet by mouth once per day with food, or as directed by your provider

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            alternatives

            What are alternatives to Magnesium oxide?

            There are a number of medications that your doctor can prescribe in place of Magnesium oxide. Compare a few possible alternatives below.
            Magnesium oxide
            Used for:
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            Calcium carbonate
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            Magnesium oxide images

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            References

            Best studies we found

            Allegiant Health. (2021). MAGNESIUM OXIDE tablet [package insert]. DailyMed.

            APNAR PHARMA LP. (2023). MAGNESIUM OXIDE tablet [package insert]. DailyMed.

            Chang, L., et al. (2023). American Gastroenterological Association-American College of Gastroenterology clinical practice guideline: Pharmacological management of chronic idiopathic constipation. Gastroenterology.

            View All References (8)

            Cunningham, J., et al. (2012). Magnesium in chronic kidney disease stages 3 and 4 and in dialysis patients. Clinical Kidney Journal.

            Guerrera, M.P., et al. (2009). Therapeutic uses of magnesium. American Family Physician.

            Lindberg, J. S., et al. (1990). Magnesium bioavailability from magnesium citrate and magnesium oxide. Journal of the American College of Nutrition.

            Mah, J., et al. (2021). Oral magnesium supplementation for insomnia in older adults: a systematic review & meta-analysis. BMC Complementary Medicine and Therapies.

            Mazza, G. R., et al. (2022). Assessing the efficacy of magnesium oxide and riboflavin as preventative treatment of migraines in pregnancy. American Journal of Obstetrics and Gynecology.

            National Cancer Institute Drug Dictionary. (n.d.). Magnesium oxide.

            Office of Dietary Supplements. (2022). Magnesium. National Institutes of Health.

            Westminster Pharmaceuticals, LLC. (2020). MAGNESIUM OXIDE tablet [package insert]. DailyMed.

            GoodRx Health has strict sourcing policies and relies on primary sources such as medical organizations, governmental agencies, academic institutions, and peer-reviewed scientific journals. Learn more about how we ensure our content is accurate, thorough, and unbiased by reading our editorial guidelines.
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