The use of vasopressin receptor antagonists in hyponatremia.

INTRODUCTION: Considerable data have recently characterized hyponatremia as fairly common in the intensive care and general hospital settings. Moreover, mounting evidence suggests the association of mild degrees of hyponatremia with untoward neurocognitive and musculoskeletal outcomes. A key development in our ability to treat hyponatremia was the introduction and approval of aquaretics (vaptans). These vasopressin receptor antagonists work by increasing electrolyte-free water excretion and thus raising serum sodium concentration. AREAS COVERED: This review presents a diagnostic approach for hyponatremia and discusses some therapeutic considerations. It displays new evidence linking mild chronic hyponatremia with unfavorable outcomes and examines the available treatment options and their limitations and strengths. New data on vaptans and their potential role to treat hyponatremia in different clinical settings are reviewed. EXPERT OPINION: Vaptans are likely to play an important role in treating hyponatremia, given their clinical efficacy and tolerability. High cost remains an impediment for vaptans, and more studies are needed to further define their best use in hyponatremic patients.