Hyponatremia is a potentially serious condition in which the level of sodium in the blood is too low. An imbalance is created when there is too little sodium for the amount of water in the body. As a result, water moves into the body’s cells causing them to swell.
There are different types of hyponatremia, each resulting in low sodium in the body:
|Euvolemic hyponatremia||Water level increases, but sodium level stays the same|
|Hypervolemic hyponatremia||Water and sodium levels increase, but the water gain is greater|
|Hypovolemic hyponatremia||Water and sodium levels decrease, but the sodium loss is greater|
Hyponatremia may be caused by:
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Factors that may increase your risk of developing hyponatremia include:
People with mild hyponatremia usually don't have symptoms. As hyponatremia progresses, symptoms will appear and worsen .
Moderate to severe hyponatremia may cause:
Your doctor will ask about your symptoms and medical history. A physical exam will be done. Your doctor will ask you about your fluid intake and do some tests.
Tests may include:
Other tests may be done to look for any underlying causes of your hyponatremia.
Treatment may depend on:
In most cases, your doctor will want to correct the sodium level slowly. Serious complications may occur when sodium levels rise too rapidly.
Treatment options may include:
To help reduce your chance of getting hyponatremia, take these steps:
American Society forNutriton
National Institute of Diabetes and Digestive and Kidney Diseases
The College of Family Physicians of Canada
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Last reviewed November 2013 by Michael Woods, MD
Last Updated: 11/15/2013