American Research Journal of Pharmacy

What is Known and Objective: Acute hyponatremia occurs when serum sodium declines to <135 mEq/L within a 48-hour period. Tolvaptan, a vasopressin receptor antagonist, causes aquaresis without increased sodium loss. Details of the Case: A77 year-old male, with a history of glioblastoma, presented with a five-day history of weakness. Serum sodium on admission was 115 mEq/L, and normal saline was started. The following morning serum sodium was 114 mEq/L. Tolvaptan 15mg was given. By hospital day 3, the serum sodium increased to 124 mEq/L following titrated tolvaptan doses. What is New and Conclusion: Based on these results, tolvaptan may have a role in the treatment of acute hyponatremia.