[Hyponatraemia in elderly patient - significance, clarification and therapy].

In the general population, the prevalence of mild, usually asymptomatic hyponatremia ranges from 1,7-7,7 %. With increasing age, it rises to 11,6 % in > 75-year-olds. The prevalence is much higher in nursing home residents and hospital patients. Hyponatremia thus represents the most common electrolyte disturbance in the elderly. Despite the existing evidence on the acute as well as chronic effects of hyponatremia, too little attention is paid to it in clinical practice. An algorithm has proven to be useful for the diagnosis of hyponatremia, which enables the cause to be identified in a few simple steps and at the same time leads to the correct therapeutic steps. The goal must be a serum sodium within the normal range. This is the only way to improve the prognosis and functionality of elderly patients. For SIADH, we have a potent substance available in tolvaptan. In order to be able to recognize the danger of overcorrection in time, the adjustment should take place in the inpatient setting.