Metolazone is used for controlling high blood pressure and treating fluid retention. The drug cannot cure these conditions, but it can help increase the amount of water and salt the kidneys remove from the blood. This decrease in blood volume can help lower blood pressure and help the body get rid of extra fluid. There are currently no off-label metolazone uses.
In clinical studies, metolazone has been shown to significantly lower both systolic and diastolic blood pressures. By lowering blood pressure, metolazone can decrease the risk of developing health problems, such as a stroke, heart disease, or congestive heart failure, which can occur with long-term high blood pressure(see Effects of High Blood Pressure). However, the drug is not a cure for this condition.