Tolvaptan


Tolvaptan is an aquaretic drug that functions as a selective, competitive vasopressin receptor 2 antagonist used to treat hyponatremia associated with congestive heart failure, cirrhosis, and the syndrome of inappropriate antidiuretic hormone. Tolvaptan was approved by the U.S. Food and Drug Administration on May 19, 2009, and is sold by Otsuka Pharmaceutical Co. under the trade name Samsca.
The FDA granted tolvaptan a fast-track designation for clinical trials investigating its use for the treatment of polycystic kidney disease.

Side effects

The FDA has determined that tolvaptan should not be used for longer than 30 days and should not be used in patients with underlying liver disease because it can cause liver injury, potentially leading to liver failure. When using to treat hyponatremia, it may cause too rapid correction of hyponatremia resulting in fatal osmotic demyelination syndrome.

Pharmacology

Tolvaptan is a selective V2 receptor antagonist.

Chemistry

Tolvaptan is a racemate, a 1:1 mixture of the following two enantiomers: