Diuretics are used to treat a variety of medical disorders, including heart failure, hypertension, liver disease, and some forms of renal disease. Diuretics make you pee more often and reduce your blood sodium level. Therefore, they are also called "water pills." The three main types of diuretics are thiazide, loop, and potassium sparing. Thiazides work by increasing urine production and reducing reabsorption of water and salt in the kidney. This reduces fluid accumulation in various parts of the body, such as the brain and lungs. It can also help control high blood pressure. Thiazides may be taken alone or with other medications to control diabetes or prevent kidney stones. They are used most often for treating hypertension (high blood pressure) and edema (excessive fluid buildup in the body). Loop diuretics work by interfering with how well the kidneys remove water from the body. This drug type is used to treat congestive heart failure when other treatments have failed or are not appropriate. Loop diuretics do not allow the body to produce its own fluids so they must be given intravenously or through a tube into a large vein. A dose of this medication will cause severe dehydration over time.