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:
Hyponatremia may be caused by:
Factors that may increase your chance of 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 cases when the sodium has been low for more than 1-2 days, your doctor will want to correct the sodium level slowly. Serious complications may occur when sodium levels rise too rapidly. It can be corrected more quickly if it has been lw for a short time.
Treatment options may include:
To help reduce your chance of hyponatremia:
American Society for Nutriton
National Institute of Diabetes and Digestive and Kidney Diseases
The College of Family Physicians of Canada
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Last reviewed December 2014 by Michael Woods, MD
Please be aware that this information is provided to supplement the care provided by your physician. It is neither intended nor implied to be a substitute for professional medical advice. CALL YOUR HEALTHCARE PROVIDER IMMEDIATELY IF YOU THINK YOU MAY HAVE A MEDICAL EMERGENCY. Always seek the advice of your physician or other qualified health provider prior to starting any new treatment or with any questions you may have regarding a medical condition.