Betalucil, the drug name is Metoprolol Tartrate, and the discontinuation syndrome is reflexively induced increased sympathetic excitability, which is manifested by an increased heart rate and an increased sense of pulsatile heartbeat. Metoprolol tartrate is a beta-blocker that selectively inhibits beta receptors on the heart and blood vessels, slowing the heart rate, decreasing contractility, and decreasing oxygen consumption, thus relieving heart failure symptoms and lowering blood pressure. Metoprolol tartrate, stopping the drug too quickly may appear discontinuation reaction, mainly manifested as sympathetic reflex excitability increase, the appearance of accelerated heart rate, heartbeat pulsatility enhancement, double upper limb tremor, blood pressure rise, etc., in serious cases, there may be dyspnea, coughing, decreased exercise tolerance and other aggravation of the manifestations of heart failure. Therefore, Metoprolol tartrate, should be gradually reduced under the guidance of the doctor, so that the body has sufficient time to adapt, not too fast and too fierce, in order to avoid accidents.