Furosemide, known by its brand name Lasix, is a medication called a diuretic. It is commonly used to treat conditions like high blood pressure, edema (swelling caused by excess fluid), and congestive heart failure. Furosemide works by increasing the production of urine, which helps the body get rid of extra water and salt. This can help decrease fluid buildup in the body and reduce strain on the heart. It is important to take furosemide as prescribed by a doctor and to understand the potential side effects and precautions associated with its use.