The effect of diuretics is to help the body discharge excess water by taking the drug, diuretic system in the clinical efficacy and role of a relatively wide range, especially can be applied to cardiovascular disease, for renal insufficiency patients can also be applied. Diuretics for cardiovascular disease, mainly used in the treatment of congestive heart failure, hypertension, belonging to a large class of antihypertensive drugs in the hypertension drug selection program. In addition, for heart failure diseases, whether it is left heart failure, right heart failure, or total heart failure, diuretics can be appropriately selected for application to remove excess water from the body and reduce the preload and afterload of the heart. Types of diuretics include potassium-preserving diuretics and non-potassium-preserving diuretics, so when applying diuretics, it is necessary to monitor blood ions regularly, especially according to the concentration of potassium in the blood, to control the type of diuretics and the dosage of diuretics.