Betaxolol (metoprolol) is a beta-blocker and has a wide range of applications: hypertension, coronary heart disease, heart failure, arrhythmias, hyperthyroidism, cirrhosis and other diseases can be applied. However, the drug is not a panacea, there are also side effects, so here to remind everyone to pay attention to the application of the following points: the First Affiliated Hospital of Henan College of Traditional Chinese Medicine, Department of Cardiology, Jing Yu Ma 1, patients with bronchial asthma is prohibited; 2, low blood pressure, heart rate or pulse rate of patients with slow use; 3, acute heart failure, or chronic heart failure for a short period of time aggravated by temporary use; 4, if already applied, side effects such as: weakness, lower limb cold, sexual function is reduced. 5. Metoprolol should not be discontinued suddenly, as it can cause rebound and aggravation. For example, if a patient is taking metoprolol 50mg twice a day, the dose can be reduced by taking 25mg twice a day for 1 or 2 weeks and then continue to reduce the dose according to this method. It is important to observe the reduction as you go along and seek prompt medical attention if there are any problems. In addition, the gradual addition of drugs that can replace the effect of metoprolol will help to maintain the efficacy of the treatment.