Tolvaptan
Tolvaptan increases excretion of water by blocking vasopressin V2 receptors. Its use and monitoring differ substantially between low-sodium states and autosomal dominant polycystic kidney disease.
Key points
- Tolvaptan can change fluid balance and blood sodium quickly, so thirst, access to water and laboratory monitoring are important.
- Treatment for polycystic kidney disease requires particular attention to liver injury risk and ongoing liver tests.
- Products and treatment protocols used for different indications are not automatically interchangeable.
Listings are for comparison only; suitability and supply depend on specialist assessment, indication-specific prescribing and pharmacy checks.
What tolvaptan is used for
Tolvaptan may be used in selected cases of hyponatraemia or autosomal dominant polycystic kidney disease. The treatment setting, goals and monitoring are different for each use.
How it works
Blocking vasopressin V2 receptors reduces water reabsorption in the kidneys. This can raise blood sodium in selected patients and can affect cyst-related pathways in polycystic kidney disease.
Important safety checks
The clinical team should review liver and kidney function, sodium concentration, dehydration risk, ability to sense thirst and access water, and interacting medicines. Strong enzyme inhibitors can substantially change tolvaptan exposure.
When to seek urgent care
Seek urgent help for confusion, severe weakness, fainting, inability to drink, very little urine, repeated vomiting, yellow skin or eyes, dark urine, severe upper-abdominal pain or a serious allergic reaction.