Furosemide is a diuretic commonly used in clinical practice and belongs to the group of tab diuretics. Its main mechanism of action is to achieve a diuretic effect by inhibiting the reabsorption of sodium and chloride ions by the renal tubules. Furosemide may be clinically more powerful than spironolactone and other diuretics such as hydrochlorothiazide. The starting amount of furosemide, starting from small doses, is 20mg-40mg. although the maximum dose can reach 600mg a day, the clinical dosage does not exceed 200mg. furosemide is to be avoided clinically in patients with hypotension or shock because of its diuretic effect. Furosemide is also avoided in patients with hypokalemia because of its potassium drainage effect, and is prohibited in patients with furosemide allergy. Furosemide can also be used among antihypertensive drugs because of its diuretic effect to lower blood pressure. Patients with swelling can also use furosemide to reduce swelling.