MANAGEMENT OF SEVERE HYPONATREMIA: ROLE OF TOLVAPTAN, AND THE IMPORTANCE OF SLOW CORRECTION TO PREVENT MYELINOLYSIS

Abstract

Severe hyponatremia is a frequent electrolyte disturbance in hospitalized patients and poses a significant risk of neurologic complications, especially when serum sodium correction is performed quickly. Tolvaptan, a selective antagonist of vasopressin V2 receptors, has emerged as an effective therapeutic option in the correction of euvolemic and hypervolemic hyponatremia, especially in cases of inappropriate antidiuretic hormone secretion syndrome (SIADH). The objective of this study is to analyze the efficacy of tolvaptan, in the management of severe hyponatremia, and to discuss the importance of slow correction in the prevention of osmotic demyelination syndrome (ODS). To this end, a literature review was carried out in databases such as PubMed, Scopus, Embase, Web of Science, and Cochrane Library, covering publications between 2015 and 2025. 10 studies were selected, including meta-analyses, cohort studies, randomized controlled trials, and case reports. The findings demonstrate that tolvaptan promotes a significant and rapid increase in serum sodium, but with a considerable risk of overcorrection, especially in patients with profound hyponatremia and low urea levels. Reports of SDGs, even with corrections within the limits considered safe, reinforce the need for rigorous monitoring and an individualized approach. It is concluded that tolvaptan is a valuable therapeutic tool, as long as it is used with caution, respecting the clinical and laboratory parameters of each patient.