Common causes of high blood sodium levels, or hypernatremia, include excessive consumption of salt, hyperventilation, dehydration from lack of water intake, or dehydration resulting from high fever, sweating, diarrhea or intense vomiting, according to Chemocare. Taking steroids, licorice or certain medications that lower blood pressure can also cause hypernatremia.
Hypernatremia refers to an electrolyte imbalance in which the body has sodium levels above 145 milliequivalents per liter, explains Chemocare. Normal adult sodium levels range from 136 to 145 milliequivalents per liter.
People with endocrine diseases such as aldosteronism or diabetes are also prone to hypernatremia, Chemocare states. Symptoms of high blood sodium include dizziness when standing up or changing positions, too much sweating, fever, vomiting or diarrhea. These symptoms often only manifest if an individual has considerably high blood sodium levels.
Doctors may prescribe intravenous fluids or diuretics to control blood sodium levels, advises Chemocare. Dehydrated patients receive fluids, while those with extra fluids in their bodies who continue to retain sodium in their blood typically receive loop diuretics, which work by reducing blood sodium levels and allowing the body to eliminate excess fluid through urine. Anyone who experiences serious constipation that does not resolve with the use of laxatives should contact a doctor. Severe diarrhea, nausea that affects a person's ability to eat, vomiting and muscle weakness also require medical care.