Loop pills, also known as water pills, are diuretics commonly used as medication for heart failure. They can lower blood pressure and improve circulation, by helping the body dispose of excess water and salt through urine. Diuretics are also used for other widely diagnosed conditions like high blood pressure, glaucoma and edema.

However, a recent study from Yale University found disparities between different water pills. In fact, one rarely prescribed pill was significantly more effective for heart conditions than the more commonly prescribed variations. The results of the study throw into question the pill options currently available.

"Loop diuretics are a cornerstone of heart failure treatment, so it is vital to understand the comparative effectiveness and real-world use of the drugs within this class," said Behnood Bikdeli, lead author and postdoctoral associate in cardiovascular medicine at the Yale Center for Outcomes Research and Evaluation.

Between 2009 and 2010, approximately 274,515 patients were hospitalized for heart failure and among the group, 92 percent received water pills at the hospital. Within that group, 87 percent took only one diuretic called furosemide, while three percent took bumetanide and 0.4 percent had to take torsemide . Ten percent were given a combination of the three.

In previous studies, researchers found that torsemide, the least-used water pill, lasted longer and was best tolerated, when compared to the other two pills.

"There appears to be potential benefits from using torsemide compared with furosemide, but it is rarely used in practice," said Bikdeli. "Furosemide is the dominantly used loop diuretic in practice; however, if the potential advantages of torsemide over furosemide are proven in subsequent comparative effectiveness studies, this drug might become the preferred treatment of chronic heart failure."

Torsemide, marketed as Demadex, was also the most expensive. This comparison study gives health providers a view of the potential benefits of taking torsemide over the other treatment options, and could possible change prescription practices for a staggering number of heart patients.

According to the National Heart, Lung and Blood Institute, there is no cure for heart failure and nearly 5.8 million people in the United States have the heart condition. Treatments and changes to lifestyle are the only ways to avoid complications.

The study was published in the early edition of Journal of the American College of Cardiology on April 1.