Pediatric Magnesium (Mag-Ox®) Uses and Side Effects

What Is Magnesium Oxide?

Magnesium oxide (Mag-Ox®) supplements' main uses include treating low magnesium levels in the body. The body needs magnesium for normal functioning of nerves, muscles, and cells. Lack of magnesium after a liver transplant can lead to irritability, muscle weakness, irregular heartbeat, or seizures. Magnesium-providing medications also can be used to treat heartburn, acid indigestion, or sour stomach.

Note: The best dietary sources of magnesium include green leafy vegetables, avocados, bananas, nuts, peas, beans, wheat germ, and grains. A high-fat diet causes the body to absorb smaller amounts of magnesium than normal to be absorbed. Cooking decreases the magnesium content of foods.

Magnesium Oxide Dosage

Magnesium supplements are taken orally. Magnesium oxide is available in 140-mg capsules as well as 400- and 425-mg tablets. Magnesium gluconate (Magonate®)is available in 500-mg tablets.

How to Properly Take Magnesium Oxide

Your child should swallow magnesium oxide along with a full glass of water. Do not crush or chew magnesium oxide tablets. It is best to take magnesium supplements with or just after a meal to improve absorption. Do not take tacrolimus (Prograf, FK-506).

Missed Doses

If your child misses a dose of magnesium oxide, take it as soon as you or your child remembers. However, if it is near the time for the next dose, skip the missed dose and resume your child’s usual dosing schedule. Do not double the dose to catch up.

Magnesium Oxide Side Effects

It is not uncommon to experience diarrhea, stomach upset, bloating, and gas while taking magnesium supplements. If any of these side effects persists or becomes bothersome, inform your child’s transplant doctor or transplant coordinator.

he side effects of magnesium oxide listed below occur only rarely. If your child experiences any of these, inform the doctor or coordinator immediately.

  • Nausea
  • Vomiting
  • Slow reflexes
  • Change in heart rate
  • Flushing or faintness

Magnesium Oxide Drug Interactions

Tell your coordinator about all the medication your child uses, whether over-the-counter or prescription, so you can be warned of undesirable interactions and prevent them.

How to Store

Store magnesium oxide at room temperature.

Precautions for Children and Teenagers

Your child should take magnesium supplements exactly as prescribed. Do not take tacrolimus (Prograf, FK506). Avoid taking this medication within one hour of taking medications that are coated to prevent breakdown in the stomach. Avoid taking this medication within one to two hours of taking tetracycline or quinotone antibiotics. Magnesium supplements taken soon after these medications may interfere with their absorption.

Magnesium Oxide Availability

Most pharmacies stock magnesium oxide and magnesium gluconate.

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Learn more about other Liver Transplant Drugs.