How Does Furosemide Work?

 Furosemide (Lasix^®) is a prescription medication approved for the treatment of high blood pressure. It can also be used to treat water retention caused by kidney disease or kidney failure, congestive heart failure, or cirrhosis. But how does furosemide work?

 

The medication is a diuretic, which is commonly referred to as a "water pill." Specifically, furosemide is known as a "loop diuretic," named after the part of the kidneys that it affects (the loop of Henle). It works by increasing the amount of salt and water that the kidneys remove from the blood. This extra salt and water is then passed out through the urine. By increasing the amount of water removed from the blood, furosemide causes a decrease in blood volume. Because of this effect, the drug can lower blood pressure and help with water retention.