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Hypophosphatemia (Low Level of Phosphate 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 hypophosphatemia, the level of phosphate in blood is too low.

Hypophosphatemia may be

  • Acute

  • Chronic

Acute hypophosphatemia

Chronic hypophosphatemia

In chronic hypophosphatemia, the phosphate Overview of Phosphate's Role in the Body Phosphorus is an element that plays an important role in the body. In the body, almost all phosphorus is combined with oxygen, forming phosphate. Phosphate is one of the body's electrolytes... read more level in blood becomes low over time. Chronic hypophosphatemia usually develops because too much phosphate is excreted. Causes include the following:

Did You Know...

  • Some people who survived concentration camps died because their already low phosphate level suddenly fell when they began eating a normal diet, a phenomenon called refeeding syndrome.

Symptoms of Hypophosphatemia

Symptoms of hypophosphatemia occur only when the phosphate level in blood becomes very low. Muscle weakness develops, followed by stupor, coma, and death.

In mild chronic hypophosphatemia, the bones can weaken, resulting in bone pain and fractures. People may become weak and lose their appetite.

Diagnosis of Hypophosphatemia

  • Measurement of phosphate levels in the blood

Hypophosphatemia is diagnosed when blood tests show that the level of phosphate in the blood is low. Doctors do other tests to identify the cause if it is not readily apparent.

Treatment of Hypophosphatemia

  • Increase phosphate intake

Drugs that reduce the phosphate level are stopped.

If hypophosphatemia is mild and causes no symptoms, drinking low-fat or skim milk, which provides a large amount of phosphate, may help. Or people can take phosphate by mouth, but doing so usually causes diarrhea.

If hypophosphatemia is very severe or if phosphate cannot be taken by mouth, phosphate may be given by vein (intravenously).

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