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Medical Author:

Benjamin Wedro, MD, FACEP, FAAEM

Benjamin Wedro, MD, FACEP, FAAEM

Dr. Ben Wedro practices emergency medicine at Gundersen Clinic, a regional trauma center in La Crosse, Wisconsin. His background includes undergraduate and medical studies at the University of Alberta, a Family Practice internship at Queen's University in Kingston, Ontario and residency training in Emergency Medicine at the University of Oklahoma Health Sciences Center.

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Medical Editor:

Melissa Conrad Stöppler, MD, Chief Medical Editor

Melissa Conrad Stöppler, MD, Chief Medical Editor

Melissa Conrad Stöppler, MD, is a U.S. board-certified Anatomic Pathologist with subspecialty training in the fields of Experimental and Molecular Pathology. Dr. Stöppler's educational background includes a BA with Highest Distinction from the University of Virginia and an MD from the University of North Carolina. She completed residency training in Anatomic Pathology at Georgetown University followed by subspecialty fellowship training in molecular diagnostics and experimental pathology.

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The diagnosis of hyponatremia is made by a blood test that measures the concentration of sodium in the bloodstream. The normal sodium level is between 135-145 mEq/l, and levels below 110 mEq/l constitute a true emergency.

Other tests may help decide what type of hyponatremia situation exists. The amount of sodium that is being excreted in the urine may be measured, as well as the concentration of urine. These results may guide the health care practitioner to decide whether a hypo-, hyper- or euvolemic hyponatremic situation exists and help establish the diagnosis.

The diagnosis of the cause of hyponatremia also depends upon a thorough history of the circumstances that lead to the patient's illness, and a thorough physical examination. Determining the severity of hyponatremia depends on accessing whether the sodium levels have decreased acutely, usually in less than 48 hours, or whether they have gradually decreased over a longer period of time. Since acute hyponatremia can cause potentially life-threatening brain swelling and death, it is imperative to find the reason for the hyponatremia and take appropriate action to correct it.

Past medical history, history of medication use, and recent activity, along with the blood and urine test results, will help guide the health care provider to the diagnosis and direct the treatment.

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