Hypernatremia involves dehydration, which can have many causes, including not drinking enough fluids, diarrhea, kidney dysfunction, and diuretics.
Mainly, people are thirsty, and if hypernatremia worsens, they may become confused or have muscle twitches and seizures.
Blood tests are done to measure the sodium level.
Usually, fluids are given intravenously to slowly reduce the sodium level in the blood.
(See also Overview of Electrolytes Overview of Electrolytes Well over half of the body's weight is made up of water. Doctors think about the body's water as being restricted to various spaces, called fluid compartments. The three main compartments are... read more and Overview of Sodium's Role in the Body Overview of Sodium's Role in the Body Sodium is one of the body's electrolytes, which are minerals that the body needs in relatively large amounts. Electrolytes carry an electric charge when dissolved in body fluids such as blood... read more .)
Sodium is one of the body's electrolytes, which are minerals Overview of Minerals Minerals are necessary for the normal functioning of the body’s cells. The body needs relatively large quantities of Calcium Chloride Magnesium Phosphate read more that carry an electric charge when dissolved in body fluids such as blood. In hypernatremia, the body contains too little water for the amount of sodium Overview of Sodium's Role in the Body Sodium is one of the body's electrolytes, which are minerals that the body needs in relatively large amounts. Electrolytes carry an electric charge when dissolved in body fluids such as blood... read more . The sodium level in the blood becomes abnormally high when water loss exceeds sodium loss.
Usually, hypernatremia results from dehydration Dehydration Dehydration is a deficiency of water in the body. Vomiting, diarrhea, excessive sweating, burns, kidney failure, and use of diuretics may cause dehydration. People feel thirsty, and as dehydration... read more . For example, people may lose body fluids and become dehydrated due to
Insufficient water intake usually plays an important role.
People with diabetes mellitus Diabetes Mellitus (DM) Diabetes mellitus is a disorder in which the body does not produce enough or respond normally to insulin, causing blood sugar (glucose) levels to be abnormally high. Urination and thirst are... read more and high blood sugar levels may urinate excessive amounts, causing dehydration. Dehydration can also be caused by kidney disorders and by diabetes insipidus Nephrogenic Diabetes Insipidus In nephrogenic diabetes insipidus, the kidneys produce a large volume of dilute urine because the kidney tubules fail to respond to vasopressin (antidiuretic hormone) and are unable to reabsorb... read more , which also causes people to urinate excessive amounts although without high blood sugar levels,and is due to inadequate or ineffective vasopressin secretion or action.
Rarely, adrenal gland disorders Overview of the Adrenal Glands The body has two adrenal glands, one near the top of each kidney. They are endocrine glands, which secrete hormones into the bloodstream. Each adrenal gland has two parts. Medulla: The inner... read more can cause mild hypernatremia without dehydration. Excessive administration of salt (usually in hospitalized people) is another rare cause of hypernatremia. Hypernatremia is most common among older people.
The diagnosis is based on blood tests indicating that the sodium level is high.
Doctors may do further testing to identify the cause of the hypernatremia, including measurements of urine volume and concentration. A special test called the water deprivation test Diagnosis Central diabetes insipidus is a lack of the hormone vasopressin (antidiuretic hormone) that causes excessive production of very dilute urine (polyuria). Central diabetes insipidus has several... read more is useful in identifying some causes, such as diabetes insipidus. The doctor monitors a person carefully during the 12-hour course of this test, because it is potentially dangerous.
Hypernatremia is treated by replacing fluids. In all but the mildest cases, dilute fluids (containing water and a small amount of sodium in carefully adjusted concentrations) are given intravenously. The sodium level in blood is reduced slowly because reducing the level too rapidly can cause permanent brain damage.