Hyponatremia
Tolvaptan is used to treat hyponatremia, which is low sodium levels in the blood, and autosomal dominant polycystic kidney disease, which is a genetic disorder causing kidney cysts.
Tolvaptan works by blocking vasopressin, which is a hormone that controls water balance. This helps increase sodium levels and slows the growth of kidney cysts.
Tolvaptan is usually taken as a tablet, twice daily, on an empty stomach. The starting dose is typically 15 mg, with a maximum of 60 mg twice daily, adjusted by your doctor.
Common side effects of Tolvaptan include thirst, dry mouth, and increased urination, which occur in more than 10% of users.
Tolvaptan can cause serious liver problems, so regular liver tests are needed. It's not recommended for those with liver issues or who can't sense thirst. Avoid during pregnancy and breastfeeding.
US(FDA), UK(BNF)
NO
NO
Vasopressin V2 Receptor Antagonist
NO
Tolvaptan can interact with medications that affect liver enzymes, particularly CYP3A4 inhibitors like ketoconazole, clarithromycin, or ritonavir, which may increase Tolvaptan levels in the body and raise the risk of liver damage. Conversely, CYP3A4 inducers like rifampin or phenytoin can reduce Tolvaptan's effectiveness. It may also interact with diuretics or ACE inhibitors, which affect fluid and electrolyte balance. Always consult a healthcare provider before combining Tolvaptan with other medications.