Serum sodium

Injury	Disease	Nutrition	Poison

Symptoms	Surgery	Test	Special Topic

Blood test

Overview

Risks

Results

Serum sodium

Alternative Names:

Sodium - serum; Na+
Normal Values:

The normal range is 135 to 145 mEq/L.

Note: mEq/L = milliequivalents per liter

What abnormal results mean:

text continues below

Greater-than-normal sodium levels may indicate many different conditions. To help determine the cause, your doctor will also consider the amount of fluid in your body, or total body water. The doctor does this during the physical exam by looking at things like the turgor of your skin and abnormal fluid buildup in the ankles, feet, and legs.

If the amount of fluid in your body (total body water) is low, you may have lost water due to burns, excessive sweating, diarrhea, or use of diuretics (for example, furosemide, bumetanide, or torsemide).
If your total body water is normal, having a high sodium may indicate diabetes insipidus.
If your total body water is high, this may indicate hyperaldosteronism (too much of the hormone aldosterone), Cushing's Syndrome (too much of a hormone called cortisol), or salt or sodium bicarbonate ingestion.

Lower-than-normal sodium levels also may be classified according to total body water:

Low total body water may indicate dehydration, vomiting, diarrhea, over diuresis, or ketonuria (excretion or loss of ketone bodies in urine).
Near-normal total body water may indicate SIADH, hypothyroidism (an underactive thyroid), or Addison's Disease (low production of cortisol and other hormones).
An increase in total body water may indicate congestive heart failure, nephrotic syndrome and other causes of kidney disease, or cirrhosis of the liver.

Additional conditions for which the test may be performed include: