A diuretic is a substance that removes water from the body by promoting urine formation and the loss of salt (sodium).

Caffeine and alcohol are common diuretics.

Diuretic medicines include furosemide, hydrochlorothiazide, metolazone, and spironolactone. These medicines may be used as part of treatment for conditions that cause swelling from water retention (edema), such as heart failure, hypertension, or liver or kidney disease.