Tolvaptan

Adults: Hypervolemic or euvolemic hyponatremia The usual starting dose of Tolvaptan is 15 mg once daily, and you can take it with or without meals. After at least 24 hours the dose can be increased to 30 mg once daily, and then up to a maximum of 60 mg once daily, as needed to reach the desired level of serum sodium. Don't use it for more than 30 days because of the risk of hepatotoxicity. Autosomal dominant polycystic kidney disease (ADPKD) Start with 60 mg/day in divided doses, given as 45 mg upon wakening and 15 mg 8 hours later. Then titrate according to response and tolerability, leaving at least 7 days between each titration. The first step is 90 mg/day in divided doses (60 mg upon wakening and 30 mg 8 hours later), followed by 120 mg/day in divided doses (90 mg upon wakening and 30 mg 8 hours later). Try to keep urine osmolality below 300 mOsm/kg if possible. If the maximum dose isn't tolerated, a lower dose is reasonable, with the goal of reaching a urine osmolality of 250 to 300 mOsm/kg.