Hypertensive encephalopathy refers to the symptoms caused by a sudden increase in a patient’s blood pressure in a short period of time, exceeding the brain’s own regulation. When the patient’s blood pressure exceeds 200/120 mmHg, the patient will have dizziness, lightheadedness, blurred vision, nausea, vomiting, headache, etc. The main treatment is to give blood pressure lowering. The blood pressure can be lowered to about 20% of the patient’s blood pressure on the first day, and dehydrating drugs, such as tachyphylaxis and mannitol, can be given to reduce intracranial edema. Therefore, hypertensive encephalopathy refers to the symptoms of the nervous system caused by a sharp increase in the patient’s blood pressure over a short period of time, which exceeds the brain’s own regulation.