How about the use of tolvapta in hyponatremia?

Tolvaptan. Tolvaptan can be used in treating euvolemic or hypervolemic hyponatremia and it may provide some benefit in that fluid restriction can be eased. However, the high cost and the concern for liver toxicity limit its widespread use. Also it should not be used for more than 30 days to minimize the risk of liver toxicity.
Liver Risk. Recent trial results highlight concern regarding liver toxicity: http://www. Fda. Gov/safety/medwatch/safetyinformation/safetyalertsforhumanmedicalproducts/ucm336669.Htm.
See below. Tolvaptan is a medication to improve sodium level in certain cases of hyponatremia. It is very wxpensive and used only in certain cases.