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Medical Author:

Melissa Conrad Stöppler, MD

Melissa Conrad Stöppler, MD

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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Medical Editor:

William C. Shiel Jr., MD, FACP, FACR

William C. Shiel Jr., MD, FACP, FACR

Dr. Shiel received a Bachelor of Science degree with honors from the University of Notre Dame. There he was involved in research in radiation biology and received the Huisking Scholarship. After graduating from St. Louis University School of Medicine, he completed his Internal Medicine residency and Rheumatology fellowship at the University of California, Irvine. He is board-certified in Internal Medicine and Rheumatology.

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In this Article

• What is hyponatremia (low blood sodium)?
• What causes hyponatremia (low blood sodium)?
• What are the symptoms of hyponatremia (low blood sodium)?
• How is hyponatremia diagnosed (low blood sodium)?
• How is hyponatremia treated (low blood sodium)?
• Hyponatremia At A Glance
• Patient Comments: Hyponatremia - Describe Your Experience
• Find a local Internist in your town
• Hyponatremia Index

The symptoms of hyponatremia are nonspecific, so a blood test measuring the sodium level is required to confirm the diagnosis of hyponatremia. Sometimes the medical history (such as prolonged vomiting or excessive sweating) will suggest the diagnosis. In other cases, further blood tests, urine tests, and imaging studies may be needed in order to determine the exact cause of the hyponatremia.

Mild chronic hyponatremia may not require treatment other than adjustments in diet, lifestyle, or medications. For severe or acute hyponatremia, treatment typically involves the intravenous administration of fluids and electrolytes. In this case medications are often needed that treat the underlying cause of the hyponatremia as well as medications to manage the accompanying symptoms.

• Hyponatremia refers to a low level of sodium in the blood.
  
  
• Hyponatremia may result from excess fluid in the body relative to a normal amount of sodium, or it may be due to a loss of sodium and body fluid.
  
  
• Symptoms are nonspecific and can include mental changes, headache, nausea and vomiting, tiredness, muscle spasms, and seizures.
  
  
• Severe hyponatremia can lead to coma and can be fatal.
  
  
• Treatment of hyponatremia involves intravenous fluid and electrolyte replacement, medications to manage the symptoms of hyponatremia, as well as any treatments for the underlying cause.

Reference: Harrison''s Principles on Internal Medicine, 14th edition, 2006.