Betaxolol, also known as metoprolol, its main effect is to slow down the heart rate, by slowing down the heart rate to let the heart get rest. Its side effects are as follows: 1. digestive tract: it acts on the smooth muscles of the digestive tract, and if the smooth muscles are excessively relaxed, it will produce side effects such as related stomach pain and bloating; 2. respiratory tract: if it acts on the smooth muscles of the respiratory tract, there may be adverse reactions such as shortness of breath; 3. central nervous system; 4. betaxolol slowed down the heart rate while the others were also slowed down. However, side effects of this drug are less common in clinical practice. The dosage is usually increased gradually from small to large. If the patient’s heart rate is found to be particularly slow in clinical practice, the dosage should be reduced if the heart rate is only more than 40 times per minute, because there is a risk of cardiac arrest if the heart rate is too slow.