A heart rate of 100 beats per minute to 110 beats per minute is not dangerous in most cases, it is a mild tachycardia, which may be caused by physiological or pathological reasons. 1. Physiological: If there is strenuous exercise before measuring the heart rate, or if the patient is more nervous or excited, or if the patient has consumed exciting beverages such as coffee or strong tea, it may lead to physiological tachycardia, which can be restored to normal after resting. It is a normal phenomenon, no need to worry. 2. Pathological: It may be caused by pathological factors, such as tachyarrhythmia of heart disease, systemic diseases such as anemia, hyperthyroidism, infection or fever. If left untreated, tachycardia may be further aggravated. It is recommended that the patient consult a doctor to determine the cause of tachycardia and follow the doctor’s instructions to rest or treat the primary disease, otherwise it may lead to further aggravation of tachycardia or the emergence of new symptoms.