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Magnesium oxide (By mouth)

Magnesium Oxide (mag-NEE-zee-um OX-ide)

Treats acid indigestion and upset stomach. Also used as a mineral supplement to add to the magnesium oxide in your daily diet.

Brand Name(s):

Mag-Ox 400, Nature Made Diabetes Health Pack, Phillips', UroMag

There may be other brand names for this medicine.

When This Medicine Should Not Be Used:

Unless your doctor tells you otherwise, there is no reason for you to not use this medicine.

How to Use This Medicine:

  • Take your medicine as directed.
  • Follow the instructions on the medicine label if you are using this medicine without a prescription.
  • If you are using this medicine as an antacid, do not use the medicine for longer than 2 weeks in a row.
  • Drink at least six to eight (8 ounce) cups of liquid each day, unless your doctor tells you otherwise.

If a dose is missed:

  • Take a dose as soon as you remember. If it is almost time for your next dose, wait until then and take a regular dose. Do not take extra medicine to make up for a missed dose.

How to Store and Dispose of This Medicine:

  • Store the medicine in a closed container at room temperature, away from heat, moisture, and direct light.
  • Keep all medicine out of the reach of children. Never share your medicine with anyone.
  • Ask your pharmacist, doctor, or health caregiver about the best way to dispose of any outdated medicine or medicine no longer needed.

Drugs and Foods to Avoid:

Ask your doctor or pharmacist before using any other medicine, including over-the-counter medicines, vitamins, and herbal products.

  • There are many other medicines that may not work properly if you use them together with magnesium oxide. Make sure your doctor knows about all other medicines you are using.

Warnings While Using This Medicine:

  • Make sure your doctor knows if you are pregnant or breast feeding, or if you have kidney disease.
  • Tell your doctor if your acid indigestion does not improve after using the medicine for 1 to 2 weeks.

Possible Side Effects While Using This Medicine:

If you notice these less serious side effects, talk with your doctor:

  • Diarrhea.

If you notice other side effects that you think are caused by this medicine, tell your doctor

Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088


Last Updated: 4/4/2014

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