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Hypernatremia is when there is too much sodium in the body.


Hypernatremia happens when there is an imbalance in the amount of water and sodium in the body—too little water for the amount of sodium.
The main cause of hypernatremia is having more water leave your body than enter it. This causes dehydration . A person can become dehydrated in different ways, such as:

Risk Factors

Hypernatremia is more common in older adults. Other factors that may increase your chance of hypernatremia include:
  • Fever
  • Vomiting
  • Diarrhea
  • Using certain diuretics —medications that increase urination
  • Severe burns
  • Losing too much fluid by sweating
  • Having certain medical conditions such as central diabetes insipidus or kidney disorder


Hypernatremia may cause:
  • Being thirsty
  • Dry mouth
  • Muscle weakness or muscle cramps
  • Decreased urination
  • Weight loss
  • Lightheadedness
  • Irritability
  • Confusion
  • Muscle twitching
Untreated hypernatremia can be fatal.
Dry Mouth
Dry Mouth and Throat
Dry mouth is a symptom of hypernatremia.
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You will be asked about your symptoms and medical history. You will be asked about your fluid intake and urine output. A physical exam will be done.
Your bodily fluids may be tested. This can be done with:
  • Blood tests
  • Urine tests


Fluid Replacement

Liquids can be given by mouth or IV to balance the fluids in your body. The fluid will contain a specific concentration of water, sugar, and sodium. Reintroducing fluids slowly into your body will lower the sodium to a normal level. Talk with your doctor about the best treatment plan for you.
You may also be given medication to treat nausea.


To help reduce your chance of getting hypernatremia:
  • Stay hydrated by drinking plenty of the fluids
  • Work with your doctor to manage any health conditions


Family Doctor—American Academy of Family Physicians
National Institute of Diabetes and Digestive and Kidney Diseases


The College of Family Physicians of Canada
Health Canada


Central diabetes insipidus. EBSCO DynaMed Plus website. Available at: . Updated June 7, 2017. Accessed December 18, 2017.
Dehydration and hypovolemia in adults. EBSCO DynaMed Plus website. Available at: . Updated October 5, 2015. Accessed December 18, 2017.
Hypernatremia - approach to the patient. EBSCO DynaMed Plus website. Available at: . Updated August 19, 2016. Accessed December 18, 2017.
Hypernatremia. Merck Manual Professional Edition website. Available at: Updated April 2016. Accessed January 4, 2018.
Nephrogenic diabetes insipidus. EBSCO DynaMed Plus website. Available at: . Updated June 7, 2017. Accessed December 18, 2017.

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