Normal Sodium & Potassium Blood Levels

Sodium and potassium are two electrolytes — minerals with an electric charge — that are required for the proper functioning of your cells. Your health care provider can do a test to check that you have normal sodium and potassium blood levels.

Read more: Foods Containing Electrolytes

Testing for Sodium and Potassium Blood Levels

Blood sodium and potassium levels are often checked as part of a basic metabolic panel or an electrolyte panel, along with other electrolytes, such as chloride and bicarbonate. A health care provider will take a blood sample from a vein in your arm. Typically, no special preparation is required before the test. Your health care provider will inform you if you need to temporarily stop taking any medications that could affect the results.

Your health care provider may order sodium and potassium blood tests as part of your regular checkup, to monitor an existing condition that affects electrolytes or if you have symptoms of abnormal potassium or sodium levels.

According to the U.S. National Library of Medicine, a normal potassium level is between 3.7 to 5.2 milliequivalents per liter (mEq/L) and a normal blood sodium level is between 135 to 145 mEq/L 145.

Low Sodium: Hyponatremia

What Does a High Potassium Blood Level Mean?

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In most cases of hyponatremia, "you have excess water in your body that has diluted the concentration of sodium," Dr. Weiner says. Hyponatremia may be caused by a range of conditions, including heart failure, kidney disease, adrenal problems, cirrhosis of the liver, and syndrome of inappropriate anti-diuretic hormone (SIADH), in which your body retains water instead of excreting it normally in your urine.cause:

• Hyponatremia may be caused by a range of conditions
  
• including heart failure
  
• kidney disease
  
• adrenal problems
  
• cirrhosis of the liver,
  
• syndrome of inappropriate anti-diuretic hormone (SIADH)
  
• in which your body retains water instead of excreting it normally in your urine

It can also be a side effect of certain medications, like diuretics and antidepressants.

High Sodium: Hypernatremia

An elevated blood sodium level is called hypernatremia.

Just as hyponatremia is usually the result of too much water, "if you have high sodium, then you are dehydrated — you have too little water," says Dr. Weiner. That may be due to lack of access to water or because the urge or ability to drink is impaired 6. In rare cases, it may be caused by excessive intake of salt.

Symptoms of an abnormally high blood sodium level include excessive thirst, urinating frequently, vomiting and diarrhea.

Read more: Is It Bad to Drink a Lot of Water When Dehydrated?

Low Potassium: Hypokalemia

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According to the Mayo Clinic, hypokalemia is most commonly the result of losing too much potassium in the urine due to the use of diuretic medications that increase urination 23. It may also be caused by kidney disease, eating disorders, alcoholism, certain hormonal or genetic disorders or the loss of bodily fluids from diarrhea, vomiting and sweating.cause:

• It may also be caused by kidney disease
  
• eating disorders
  
• alcoholism
  
• certain hormonal or genetic disorders or the loss of bodily fluids from diarrhea
  
• vomiting
  
• sweating

Laxatives and certain antibiotics may also cause low potassium levels.

High Potassium: Hyperkalemia

A higher-than-normal level of potassium in the blood is called hyperkalemia 2. A level higher than 6.0 mEq/L is a life-threatening condition that usually requires immediate treatment.

Hyperkalemia is most commonly caused by a problem with the kidneys. If the kidneys aren't able to remove the proper amount of potassium, it can build up in the blood. High potassium levels can also result from conditions including Addison's disease, type-1 diabetes, certain genetic disorders and burns or other traumatic injuries. It can also be a side effect of certain diuretics, antibiotics and blood pressure lowering drugs.

According to the Mayo Clinic, a potassium blood test will often come back with a falsely high level because the blood cells in the blood sample ruptured 23. A repeat test will be done if this suspected.

Read more: Symptoms of Potassium Overdose