Whether sinus tachycardia is normal or not depends on the cause of it, there are physiologic, pathologic, and pharmacologic, the former is normal, the latter two are not normal. 1. Physiological: Physiological sinus tachycardia is an “adaptive” phenomenon. It is common in healthy people, smoking, drinking tea or coffee, alcohol and tobacco, physical activity and emotional excitement. 2. Pathological: It can be seen in certain pathological states, such as fever, hyperthyroidism, anemia, shock, myocardial ischemia, congestive heart failure, etc. 3. Drugs: such as adrenaline and atropine can also cause sinus tachycardia. If the patient appears sinus tachycardia should consult the doctor in time, actively search for the cause of the disease, under the guidance of the doctor for the different causes of treatment, as soon as possible to control the condition of sinus tachycardia, to avoid long-term sinus tachycardia, the heart caused by serious adverse effects.