Sinus tachycardia is often due to sympathetic excitation. The causes of sympathetic excitation are divided into physiological and pathological. Physiological sympathetic excitation includes increased cardiac contraction after drinking alcohol, strong tea, high stress, and strenuous activity, and tachycardia can occur after sympathetic excitation. This situation does not require treatment at all and is a normal phenomenon. If the body cannot metabolize it after drinking strong coffee or tea, you can take a small amount of drugs that slow down the heart rate, such as betalactam, and it will soon return to normal. There are more cases of pathological sympathetic excitation, as follows: 1, high fever: an increase in body temperature of 1 ℃, the heart rate can increase by 10-20 beats per minute, or even 40 beats per minute, if the basal heart rate is 60-70 beats per minute, the fever can reach 100 beats per minute; 2, serious infection: when the lung function is affected, sinus tachycardia may also occur; 3, severe anemia: can be secondary to sinus tachycardia. Because when the blood volume of body circulation is not enough, it can speed up the heartbeat to help circulation; 4, hyperthyroidism; 5, heart failure. Excluding the above causes is benign sinus tachycardia. If sinus tachycardia is caused by the above causes, it is necessary to control fever, control infection, correct anemia, adjust the hormone level of hyperthyroidism, and correct heart failure.