Hyponatremia is an electrolyte imbalance in which the sodium concentration in the blood is abnormally low. This can lead to an abnormal distribution and concentration of water throughout the body. 

Causes of Hyponatremia

There are many causes of hyponatremia; including the following:

  • Diuretics, some antidepressants, and some pain medications
  • Heart failure
  • Liver or kidney problems
  • Syndrome of inappropriate antidiuretic hormone (SIADH)
  • Severe vomiting, diarrhea or sweating
  • Over-consumption of water 
  • Over-consumption of alcohol
  • Severe burns over a large area

Symptoms of Hyponatremia

Symptoms of hyponatremia tend to be more severe in acute hyponatremia (a rapid fall in sodium leves) compared to chronic hyponatremia.  Symptoms may include the following:

  • Confusion
  • Nausea and vomiting
  • Headache
  • Fatigue and loss of energy
  • Restlessness and irritability
  • Muscle weakness, cramps or spasms
  • Seizures
  • Coma

Certain people are at greater risk for hyponatremia. They include older adults; those with diseases or on medications that may precipitate an electrolyte imbalance; athletes who engage in intensive exercise; and suspected alcohol or drug abusers. For those who fall into one of these categories, hyponatremia should be suspected if one or more of the above symptoms is present.

Diagnosis of Hyponatremia

In addition to a physical examination, hyponatremia is diagnosed through blood and urine tests. These tests are essential because the symptoms of hyponatremia are common to a variety of other ailments.

Treatment of Hyponatremia

In mild cases of hyponatremia, reducing fluid intake may be all that is necessary to bring sodium levels back to normal. More severe cases can require further medication, administration of intravenous saline, or hormone therapy.

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