Hyponatremia is a frequent complication of advanced
cirrhosis with
ascites associated with increased morbidity and mortality. It is caused by an impairment in the renal capacity to eliminate solute-free water and is considered to be related to persistent secretion of
vasopressin despite low serum osmolality. This nonosmotic release of
vasopressin is mediated by the autonomic nervous system, which senses the underfilling of arterial vascular component. This reduction of effective arterial blood volume is closely related to the development of
ascites. Although the short-time effects of
vasopressin V2 receptor antagonists (vaptans) on
hyponatremia and
ascites have been repeatedly reported, their effects on the long-term management of cirrhotic
ascites have not been established yet. Considering that their effects on water diuresis and their safety are limited by severe underfilling state of patients, cautious approaches with adequate monitoring are needed to advanced
cirrhosis. Proper indication, adequate doses and new possibility of combination
therapy should be explored in the future controlled study. As
hyponatremia is frequent obstacle to
ascites management, judicious combination with low-dose
diuretics may decrease the incidence of refractory
ascites. Although vaptans show much promise in the treatment of advanced
cirrhosis, the problem of high cost should be solved for the future.