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Medically reviewed by Last updated on Aug 31, 2022.

What is hypernatremia?

Hypernatremia occurs when there is an imbalance of sodium and water in your body. The amount of sodium (salt) in your blood is higher than normal. Sodium is an electrolyte (mineral) that helps your muscles, heart, and digestive system work properly. It helps control blood pressure and fluid balance. Hypernatremia can become life-threatening if left untreated.

What may increase my risk for hypernatremia?

Your sodium level may increase if you get too much sodium through food, antacids that have sodium, or tube feeding. Hypernatremia may also occur when too much water leaves your body and you become dehydrated. Dehydration can be caused by not drinking enough water or by losing body fluid through excessive sweating or urination. Infants and the elderly are at increased risk of hypernatremia. The following may also increase your risk of hypernatremia:

  • For infants, low intake of breast milk or intake of formula that was not mixed properly
  • Decreased sense of thirst, which may occur among the elderly
  • Severe diarrhea or vomiting
  • Fever
  • Certain types of diuretics
  • Uncontrolled diabetes
  • Conditions such as diabetes insipidus, kidney failure, and Cushing syndrome
  • Severe burns

What are the signs and symptoms of hypernatremia?

  • High-pitched cry, muscle weakness, or unusual irritability or drowsiness in infants
  • Headache, confusion, or irritability
  • Drowsiness
  • Seizures
  • Muscle weakness or twitching
  • Breathing faster than normal
  • Nausea and vomiting
  • Intense thirst
  • Dry eyes or mouth

How is hypernatremia diagnosed?

Your healthcare provider will ask you about the medicines you take and your symptoms. Tell your provider how much liquid you drink and if you have been urinating more often recently. Your provider will do a physical exam to look for signs of dehydration. You may need also need any of the following:

  • Blood and urine tests will be done to check the level of sodium in your blood and urine. Blood tests may also be done to find the cause of your hypernatremia.
  • A neurologic exam tells healthcare providers if hypernatremia is affecting your brain. Healthcare providers will check how your pupils react to light. They may check your memory, balance, and hand grasp.

How is hypernatremia treated?

Treatment depends on the cause of your hypernatremia and how severe it is. You will receive liquids by mouth or through an IV to help balance your level of water and sodium. You will also receive treatment for any conditions that caused your hypernatremia.

When should you contact your healthcare provider?

  • Your baby has a high-pitched cry, muscle weakness, or unusual irritability or drowsiness.
  • You have dry eyes or mouth.
  • You have nausea, and you are vomiting.
  • You have muscle weakness or twitching.
  • You have a headache, confusion, irritability, or any other changes in behavior.
  • You are extremely drowsy.
  • You have questions or concerns about your condition or care.

When should you or someone close to you seek immediate care or call 911?

  • You have a seizure.
  • You cannot be awakened.
  • You are breathing faster than normal.

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