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Hypomagnesemia (Low Level of Magnesium in the Blood)


James L. Lewis III

, MD, Brookwood Baptist Health and Saint Vincent’s Ascension Health, Birmingham

Last full review/revision Apr 2020| Content last modified Apr 2020
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In hypomagnesemia, the level of magnesium in blood is too low.

Causes of Hypomagnesemia

Usually, the magnesium level becomes low because people consume less (most often, because of starvation) or because the intestine cannot absorb nutrients normally (called malabsorption Overview of Malabsorption Malabsorption syndrome refers to a number of disorders in which nutrients from food are not absorbed properly in the small intestine. Certain disorders, infections, and surgical procedures can... read more ). But sometimes hypomagnesemia develops because the kidneys or intestine excrete too much magnesium.

Hypomagnesemia may also result from the following:

Symptoms of Hypomagnesemia

Hypomagnesemia may cause nausea, vomiting, sleepiness, weakness, personality changes, muscle spasms, tremors, and loss of appetite. If severe, hypomagnesemia can cause seizures Seizure Disorders In seizure disorders, the brain's electrical activity is periodically disturbed, resulting in some degree of temporary brain dysfunction. Many people have unusual sensations just before a seizure... read more , especially in children.

Diagnosis of Hypomagnesemia

Treatment of Hypomagnesemia

  • Magnesium

Magnesium is given by mouth when the deficiency causes symptoms or persists. People with alcoholism are usually given magnesium.

If a very low magnesium level is causing severe symptoms or if people cannot take magnesium by mouth, magnesium is given by injection into a muscle or vein.

When treating hypomagnesemia, doctors also must correct other electrolyte abnormalities, such as hypocalcemia and hypokalemia.

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