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Hypomagnesemia is a condition in which the amount of magnesium in the blood is lower than normal.


Hypomagnesemia can be caused by:

  • Alcoholism
  • Burns that affect a large area of the body 
  • Chronic diarrhea
  • Excessive urination (polyuria), such as in uncontrolled diabetes and during recovery from acute kidney failure 
  • High blood calcium levels (hypercalcemia)
  • Hyperaldosteronism
  • Malabsorption syndromes, such as celiac disease and inflammatory bowel disease
  • Malnutrition
  • Medications including amphotericin, cisplatin, cyclosporine, diuretics, proton pump inhibitors, and aminoglycoside antibiotics
  • Sweating


Common symptoms include:

  • Abnormal eye movements (nystagmus)
  • Convulsions
  • Fatigue
  • Muscle spasms or cramps
  • Muscle weakness
  • Numbness

Exams and Tests

Your health care provider will do a physical exam to help determine the cause of your symptoms.

Tests that may be ordered include an

Blood and urine tests that may be done include:


Treatment depends on the type of hypomagnesemia and may include:

  • Fluids given through a vein (IV)
  • Magnesium by mouth or through a vein
  • Medication to relieve symptoms

Outlook (Prognosis)

The outcome depends on the condition that is causing the problem.

Possible Complications

When to Contact a Medical Professional

Hypomagnesemia can be a life-threatening emergency. Call your health care provider right away if you have symptoms of this condition.


Treating the condition that is causing hypomagnesemia can help. If you play sports, drink fluids such as sports drinks, which contain electrolytes. Drinking only water while you are active can lead to hypomagnesemia.

Alternative Names

Low blood magnesium; Magnesium - low


Yu ASL. Disorders of magnesium and phosphorous. In: Goldman L, Schafer AI, eds. Goldman’s Cecil Medicine. 24th ed. Philadelphia, Pa.: Elsevier Saunders; 2011:chap 121.

Update Date 4/14/2013

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