This is due to the abnormal regulation of the cerebral blood vessels caused by the excessive perfusion of blood in the brain after high blood pressure, so that the patient will have a headache. However, some patients do not necessarily have pain at the back of the head, and some patients may have pain in the temples. There are also some patients with hypertension who have no symptoms at all. For example, I met a patient in the clinic who had a high blood pressure of 200 mmHg and a low pressure of 100 mmHg, and I asked her what was wrong with her. This kind of patient is actually more frightening because she thinks she is fine and she will not pay attention to it. Later, I repeatedly explained to her the pros and cons of it, saying that she needs further examination because she is only 36 years old. She was later hospitalized and no cause was found for the onset after further examination, so primary hypertension was still considered and she was advised to take blood pressure lowering medication for life. It is clinically recommended that patients with hypertension should try to control their blood pressure to below 140/90 mmHg, and if they have other co-morbidities, such as those with co-morbid diabetes or poor kidney function, their blood pressure should also be controlled even lower, to 130/80 mmHg.