magnesium oxide

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Pronunciation: mag NEE see um OCK side

Brand: Mag-200, Mag-Ox 400, MagGel, Uro-Mag

What is the most important information I should know about magnesium oxide?

Before taking magnesium oxide, tell your doctor if you have any other medical conditions, allergies, or if you take other medicines or other herbal/health supplements. Magnesium oxide may not be recommended in some situations.

What is magnesium oxide?

Magnesium is a naturally occurring mineral. Magnesium is important for many systems in the body especially the muscles and nerves.

Magnesium oxide is used as a supplement to maintain adequate magnesium in the body.

Magnesium oxide may also be used for purposes other than those listed in this medication guide.

Who should not take magnesium oxide?

Do not take magnesium oxide without first talking to your doctor if you have kidney disease.

Before taking magnesium oxide, tell your doctor if you have any other medical conditions, allergies, or if you take other medicines or other herbal/health supplements. Magnesium oxide may not be recommended in some situations.

It is not known whether magnesium oxide will harm an unborn baby. Do not take magnesium oxide without first talking to your doctor if you are pregnant or planning a pregnancy.

It is not known whether magnesium oxide will harm an nursing baby. Do not take magnesium oxide without first talking to your doctor if you are breast-feeding a baby.

How should I take magnesium oxide?

Take magnesium oxide exactly as directed by your doctor or as directed on the package. If you do not understand these directions, ask your pharmacist, nurse, or doctor to explain them to you.

Take the tablets and capsules with a full glass of water.

To ensure that you get the correct dose, measure the liquid form of magnesium with a dose-measuring spoon or cup, not with a regular table spoon. If you do not have a dose-measuring device, ask your pharmacist where you can get one.

Do not take more magnesium oxide than is directed.

Store magnesium oxide at room temperature away from moisture and heat.

What happens if I miss a dose?

Take the missed dose as soon as you remember. However, if it is almost time for the next dose, skip the dose you missed and take only the next regularly scheduled dose. Do not take a double dose of this medication.

What happens if I overdose?

Seek emergency medical attention.

Symptoms of an magnesium oxide overdose include nausea, vomiting, flushing, low blood pressure, a slow heartbeat, drowsiness, coma, and death.

What should I avoid while taking magnesium oxide?

There are no restrictions on food, beverages, or activity while taking magnesium oxide unless otherwise directed by your doctor.

What are the possible side effects of magnesium oxide?

Stop taking magnesium oxide and seek emergency medical attention if you experience an allergic reaction (difficulty breathing; closing of your throat; swelling of your lips, tongue, or face; or hives).

Other, less serious side effects may be more likely to occur. Continue to take magnesium oxide and talk to your doctor if you experience diarrhea or an upset stomach.

Side effects other than those listed here may also occur. Talk to your doctor about any side effect that seems unusual or that is especially bothersome. You may report side effects to FDA at 1-800-FDA-1088.

What other drugs will affect magnesium oxide?

Before taking magnesium oxide, talk to your doctor if you are taking

  • a tetracycline antibiotic such as tetracycline (Sumycin, Achromycin V, and others), demeclocycline (Declomycin), doxycycline (Vibramycin, Monodox, Doxy, and others), minocycline (Minocin, Dynacin, and others), or oxytetracycline (Terramycin, and others);
  • a fluoroquinolone antibiotic such as ciprofloxacin (Cipro), ofloxacin (Floxin), enoxacin (Penetrex), norfloxacin (Noroxin), sparfloxacin (Zagam), levofloxacin (Levaquin), lomefloxacin (Maxaquin), grepafloxacin (Raxar), and others;
  • penicillamine (Cuprimine);
  • digoxin (Lanoxin, Lanoxicaps); or
  • nitrofurantoin (Macrodantin, Furadantin, others).

You not be able to take magnesium oxide, or you may require a dosage adjustment or special monitoring during your treatment if you are taking any of the medicines listed above.

Drugs other than those listed here can also interact with magnesium oxide. Talk to your doctor and pharmacist before taking any over-the-counter or prescription medicines.

Where can I get more information?

Your pharmacist has additional information about magnesium oxide written for health professionals that you may read.


Remember, keep this and all other medicines out of the reach of children, never share your medicines with others, and use this medication only for the indication prescribed.

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