What is a sodium blood test?

A sodium blood test measures the amount of sodium in your blood. Sodium is a type of electrolyte. Electrolytes are electrically charged minerals that help maintain fluid levels and the balance of chemicals in your body called acids and bases. Sodium also helps your nerves and muscles work properly.

You get most of the sodium you need in your diet. Once your body takes in enough sodium, the kidneys get rid of the rest in your urine. If your sodium blood levels are too high or too low, it may mean that you have a problem with your kidneys, dehydration, or another medical condition.

What is it used for?

A sodium blood test may be part of a test called an electrolyte panel. An electrolyte panel is a blood test that measures sodium, along with other electrolytes, including potassium, chloride, and bicarbonate.

Why do I need a sodium blood test?

Your health care provider may have ordered a sodium blood test as part of your regular checkup or if you have symptoms of too much sodium (hypernatremia) or too little sodium (hyponatremia) in your blood.

Symptoms of high sodium levels (hypernatremia) include:

• Excess thirst
• Infrequent urination
• Vomiting
• Diarrhea

Symptoms of low sodium levels (hyponatremia) include:

• Weakness
• Fatigue
• Confusion
• Muscle twitching