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Electrolyte: Magnesium (Mg)
Magnesium is an often forgotten electrolyte that is involved with a variety of metabolic activities in the body, including relaxation of the smooth muscles that surround the bronchial tubes in the lung, skeletal muscle contraction, and excitation of neurons in the brain. Magnesium acts as a cofactor in many of the body's enzyme activities.
Magnesium levels in the body are closely linked with sodium, potassium, and calcium metabolism; and are regulated by the kidney. Magnesium enters the body through the diet, and the amount of the chemical that is absorbed depends upon the concentration of magnesium in the body. Too little magnesium stimulates absorption from the intestine, while too much decreases the absorption.
Conditions of Magnesium Imbalance
Hypomagnesemia, too little magnesium in the blood stream, may occur because of many reasons. Some have to do with dietary deficiencies, inability of the intestine to absorb the chemical, or due to increased excretion. Common causes of low magnesium include alcoholism and its associated malnutrition, chronic diarrhea, and medications like diuretics (water pills used to control high blood pressure). More than half of hospitalized patients in ICUs may become magnesium deficient.
Hypermagnesemia describes too much magnesium in the blood stream and most often occurs in patients with kidney function problems in which the excretion of magnesium is limited. In these patients, too much magnesium intake in the diet or from magnesium-containing medications like milk of magnesia or Maalox may cause elevated magnesium levels. Since the absorption and excretion of magnesium is linked to other electrolytes, other diseases may be associated with high magnesium levels, including diabetic ketoacidosis, adrenal insufficiency, and hyperparathyroidism. Hypermagnesemia is often associated with hypocalcemia (low calcium) and hyperkalemia (high potassium).
Symptoms can include heart rhythm disturbances, muscle weakness, nausea and vomiting, and breathing difficulties.
Medically Reviewed by a Doctor on 10/25/2016
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