Gross P, Pusl T. Hyponatremia is a common electrolyte disorder that arises from disturbances in water metabolism. In cases of acute advanced hyponatremia, serious symptoms are predominant, while chronic mild hyponatremia causes minor symptoms such as slowness, depression or unsteadiness of gait. Any therapy of hyponatremia depends on the severity of its symptoms and on its specific etiology and diagnosis.