Furosemide and spironolactone together do not need additional potassium supplementation in principle, but when taking diuretics for a long period of time, you should pay attention to regular monitoring of blood potassium in the hospital, and decide according to the level of your own blood potassium, and if you have hypokalemia, you need to supplement potassium. Furosemide is a potent diuretic, which can increase the excretion of water, sodium and potassium, etc. Sodium and potassium ions will be excreted while diuretic. Spironolactone is a potassium-preserving diuretic, but has a weaker diuretic effect. Taking the two together can not only strengthen the diuretic effect, but also prevent the adverse reactions such as hypokalemia and hyperkalemia that occur during the diuretic process. Therefore, in principle, the two drugs taken together do not require additional potassium supplementation. However, even if the two are taken together, the probability of hyperkalemia or hypokalemia is not low. Therefore, attention should be paid to regular monitoring of blood potassium when taking furosemide and spironolactone for a long period of time.