INTRODUCTION. Evaluation and optimization of volume status is an essential component of treatment in patients with systolic or diastolic heart failure (HF). Removal of excess extracellular fluid with diuretics to treat peripheral and/or pulmonary edema is one of the mainstays of volume management. (See Use of angiotensin converting enzyme inhibitors in heart failure with reduced ejection fraction and Use of angiotensin II receptor blocker in heart failure with reduced ejection fraction and Use of angiotensin receptor-neprilysin inhibitor in heart failure with reduced ejection fraction.) Lasix is used to treat fluid retention in people with congestive heart failure, liver disease, or a kidney disorder such as nephrotic syndrome. Lasix is also used to treat high blood pressure (hypertension). Lasix, one of the most commonly prescribed medications for heart failure, belongs to a class of medications known as loop diuretics. Often referred to as a “water pill,” Lasix triggers the kidneys to remove water from the body by increasing urination. has been used to treat patients with heart failure and fluid retention, but the evidence base is not secure, and its place in clinical practice is yet to be estab- Describes the medication furosemide (Lasix), a drug used to treat excessive fluid accumulation and swelling (edema) of the body caused by heart failure, cirrhosis, chronic kidney failure, and nephrotic syndrome. Read more about the prescription drug furosemide (Lasix). Using Lasix for congestive heart failure can help with fluid retention by allowing the body to get rid of the extra fluid. The medicine does not cure CHF, however, or other conditions that cause the body to retain fluid. Review Article from The New England Journal of Medicine — Diuretic Treatment in Heart Failure Furosemide is used to treat fluid build-up and swelling caused by congestive heart failure, liver cirrhosis, or kidney disease. Learn about side effects, interactions and indications. This is a focused review by Anthony Busti, MD, PharmD on reasons why we use furosemide IV instead of by mouth in patients with congestive heart failure.