Hypernatremia involves dehydration, which can have many causes, including not drinking enough fluids, diarrhea, kidney dysfunction, and taking 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 More than half of a person's body weight is water. Doctors think about water in the body as being restricted to various spaces, called fluid compartments. The three main compartments are Fluid... 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 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
Drinking too little
Using diuretics (medications that increase urination)
Insufficient water intake usually plays an important role. To maintain water balance, healthy adults should consume at least 6 glasses (about 1½ quarts, or 2 liters) of fluid a day. Total fluid intake includes drinking water or other beverages, as well as eating foods with a high water content, such as fruits, vegetables, and soup. Drinking too much is usually better than drinking too little, because excreting excess water is much easier for the body than conserving water. It is possible to drink too much but, for a healthy adult, the volume of fluid intake would have to be extreme (such as over 20 liters/day). When the kidneys are functioning normally, the body can handle wide variations in fluid intake.
Did You Know...
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. Symptoms of diabetes may... read more and high blood sugar levels may urinate excessive amounts, causing dehydration. Dehydration can also be caused by kidney disorders and by arginine vasopressin resistance (formerly called nephrogenic 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 adults.
Symptoms of Hypernatremia
Hypernatremia typically causes thirst. The most serious symptoms of hypernatremia result from brain dysfunction. Severe hypernatremia can lead to confusion (delirium Delirium Delirium is a sudden, fluctuating, and usually reversible disturbance of mental function. It is characterized by an inability to pay attention, disorientation, an inability to think clearly... read more ), muscle twitching (myoclonus Myoclonus Myoclonus refers to quick, lightning-like jerks (contractions) of a muscle or a group of muscles. Myoclonus may occur normally (for example, jerking of a leg when a person is falling asleep)... read more ), seizures Seizure Disorders In seizure disorders, the brain's electrical activity is periodically disturbed, resulting in some degree of temporary brain dysfunction. Many people have unusual sensations just before a seizure... read more , coma Stupor and Coma Stupor is unresponsiveness from which a person can be aroused only by vigorous, physical stimulation. Coma is unresponsiveness from which a person cannot be aroused and in which the person's... read more , and death.
Diagnosis of Hypernatremia
Measurement of sodium level in the blood
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 Argininevasopressin deficiency (central diabetes insipidus) is a lack of the hormone vasopressin (antidiuretic hormone) that causes excessive production of very dilute urine (polyuria). Argininevasopressin... read more is useful in identifying some causes, such as argininevasopressin resistance. The doctor monitors a person carefully during the 12-hour course of this test, because it is potentially dangerous.
Treatment of Hypernatremia
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.