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is a condition that develops when the amount of magnesium in your body is too high. Magnesium is a mineral that helps your heart, muscles, and nerves work normally. It also helps strengthen your bones.

Signs and symptoms:

You may not have any signs and symptoms when your levels are only slightly above normal. As your blood levels of magnesium increase, you may have any of the following:

  • Nausea and vomiting
  • Muscle weakness
  • Facial flushing (warmth and redness)
  • Slow or irregular heartbeat
  • Headache
  • Drowsiness, lightheadedness, dizziness, or fainting
  • Slowed reflexes
  • Breathing slower than usual
  • Muscle paralysis

Have someone call 911 for any of the following:

  • You cannot be woken.
  • You cannot move your arms or legs.

Seek care immediately if:

  • Your heart is beating slower than usual, or you have an irregular heartbeat.
  • You feel extremely drowsy.
  • You have muscle weakness or slow reflexes.
  • You feel lightheaded or faint.
  • Your breathing is slower than usual, or you have trouble breathing.

Contact your healthcare provider if:

  • You have nausea and are vomiting.
  • You have questions or concerns about your condition or care.


depends on the cause of your hypermagnesemia. You may need to stop taking supplements or medicines that contain magnesium. You may need treatment for medical conditions that are causing increased levels of hypermagnesemia. Dialysis may be needed if you have kidney failure. Dialysis is a treatment to remove chemicals and waste from your blood when your kidneys can no longer do this.

Prevent hypermagnesemia:

  • If you have kidney disease, ask what medicines you can take. Some medicines contain magnesium, or they can affect your magnesium levels. Laxatives and enemas contain magnesium. Your kidneys may not be able to get rid of the magnesium from these and you may develop hypermagnesemia.
  • If you take prescription pain medicine, ask about enemas and laxatives. Prescription pain medicine slows your digestive system and may increase the amount of magnesium your body absorbs. The combined use of pain medicine and enemas or laxatives may increase your blood levels of magnesium.
  • Take magnesium supplements and antacids as directed. Your blood levels of magnesium may get too high if you take more than the recommended amount.
  • Keep magnesium supplements and antacids out of the reach of children. Your child may have an overdose of magnesium if he or she takes these.

Follow up with your healthcare provider as directed:

Write down your questions so you remember to ask them during your visits.

© 2017 Truven Health Analytics Inc. Information is for End User's use only and may not be sold, redistributed or otherwise used for commercial purposes. All illustrations and images included in CareNotes® are the copyrighted property of A.D.A.M., Inc. or Truven Health Analytics.

The above information is an educational aid only. It is not intended as medical advice for individual conditions or treatments. Talk to your doctor, nurse or pharmacist before following any medical regimen to see if it is safe and effective for you.