FRIDAY, May 9, 2008 (HealthDay News) -- A new class of drugs called vaptans may be able to treat a wide variety of conditions including painful periods, brain hemorrhage, psychotic disorders and glaucoma, Belgian researchers report.
Vaptans, short for vasopressin-receptor antagonists, work by targeting the vasopressin hormone system, which plays an important role in controlling blood and water volume in the body. These drugs, which can be taken orally or intravenously, block the action of vasopressin, according to the report in the May 10 issue of The Lancet.
In the report, Dr. Guy Decaux, from Erasmus University Hospital in Brussels, and his colleagues reviewed the current state of vaptans, of which there are several subclasses, that have been development or are under development.
Among these new drugs are relcovaptan, which has shown initial positive results in treating painful periods, as well as Raynaud's disease, which affects blood flow to the arms and legs, and tocolysis, (premature labor, leading to premature birth).
Another subclass of vaptans that include mozavaptan, lixivaptan, satavaptan and tolvaptan are diuretics, which remove water from the body, while maintaining the body's electrolyte, or salt mineral, balance. Other diuretics don't maintain the body's electrolyte balance, the researchers noted.
Some vaptans can be used to treat hyponatremia, which is a life-threatening loss of salt. Currently, conivaptan is the only vaptan approved by the U.S. Food and Drug Administration for treating hyponatremia.
Other vaptans in development might be used to treat kidney failure, diabetic nephropathy, a progressive kidney disease associated with diabetes, cirrhosis and depression, the researchers wrote.
In addition, early studies of vaptans for treating glaucoma, Meniére's disease-- an inner ear condition affecting hearing and balance -- brain hemorrhage, and small-cell lung cancer, have had promising results, Decaux's team noted.
Despite these promising results, one expert isn't ready to called vaptans a miracle cure yet.
"This is nice review of an emerging class of drugs," said Dr. Gary S. Francis, director of the coronary intensive care unit at the Cleveland Clinic. "But it is a little early to know if they will prove to be highly useful."
More information
For more on conivaptan, visit the U.S. Food and Drug Administration.
