Tachycardia is a type of medullary diuretic that can be used in patients with heart failure and generalized edema. There are two types of drugs: oral drugs and intravenous drugs. Oral drugs usually take effect in 30-60 minutes after application, peak in about two hours and last for 6-8 hours. Intravenous medications have a faster onset of effect and a slightly shorter duration of action, lasting 3-4 hours. Diuretics are a double-edged sword, can reduce the patient’s heart failure, edema, but long-term application can also cause electrolyte disorders, such as low sodium, low chlorine, low potassium, and low blood pressure, serious shock can occur, arrhythmia. Therefore, during the application of diuretics, the electrolyte situation must be closely monitored to avoid electrolyte disorders. Generally, tachycardia and spironolactone are recommended to be taken at the same time, because spironolactone can play a role in preserving potassium and reduce the probability of hypokalemia.