Calcium polystyrene sulfonate is applied for a period of time ranging from one day to several days, and some patients with high potassium due to uremia even need to take it for a long period of time. Calcium polystyrene sulfonate bulk is a potassium-lowering drug, which is able to adsorb potassium ions in the intestinal tract and thus lower blood potassium. The exact number of days to be taken needs to be determined according to the cause of hyperkalemia and the blood potassium concentration of the patient. Hyperkalemia caused by acute renal failure may take one to several days to normalize the blood potassium, while hyperkalemia caused by uremia may take a longer time, and some patients may even need to take it for life. The common adverse reactions of this drug are nausea, constipation, loss of appetite and other digestive reactions, as well as hypokalemia, this product is prohibited in patients with low potassium or high calcium, due to the ability of this drug to reduce the serum potassium ion concentration, which can enhance the effect of digitalis toxicity, and the combination of the two need to be closely monitored potassium ions. The drug should be used under the guidance of a doctor, do not use on their own.