The main reasons for this phenomenon are as follows: 1. After a part of hypertensive patients change their treatment plan, a sudden and significant drop in blood pressure can occur at a certain moment due to the accumulation of drugs, resulting in hypotensive reactions; 2. 2, due to ischemia, excessive emotional excitement, or vagal reflexes due to postural changes, can also lead to a sudden drop in high pressure, and some patients will be accompanied by a slowed heart rate. The sudden drop in high pressure should be actively sought by a doctor to analyze the cause, whether it is caused by drugs or by vagal reflexes, so as not to delay the condition and make the blood pressure lower and lower, thus endangering the patient’s life. In addition, a sudden drop in high pressure in some patients needs to be differentiated from shock. If it is a real shock, it may bring danger to the patient. Therefore, once a sudden drop in high pressure occurs, one should go to the emergency department.