Tachycardia is normal when you take medication, and the heart rate will be high when you stop taking medication. You need to make sure that it is sinus or non-sinus tachycardia, and treat it with regular medication and electrical cardioversion. Sinus tachycardia: If you don’t take medication for a long time, your heart function will be impaired, so usually doctors will prescribe medication to control the heart rate for patients to take, such as metoprolol succinate, etc., after taking the medication, the heart rate will drop to normal, but you need to insist on taking the medication, such as stopping the medication suddenly, which will cause reflexive acceleration of the heart rate. Non-sinus tachycardia: If supraventricular tachycardia or ventricular tachycardia is accompanied by cardiac hemodynamic instability (e.g., low blood pressure, heart failure, etc.), electrical cardioversion should be considered. Tachycardia needs to be seen in hospital as soon as possible to clarify the condition and develop a treatment plan as soon as possible.