Cerebral edema due to massive cerebral infarction or cerebral hemorrhage usually lasts for about half a month, with the peak of edema on day 3-7 of onset, and the edema symptoms will gradually subside as the onset time increases. Milder cerebral infarcts may be free of cerebral edema. Cerebral edema is common in a variety of neurological diseases, such as cerebral infarction, cerebral hemorrhage, brain tumor, intracranial infection, carbon monoxide poisoning, craniocerebral trauma, epileptic seizures and ischemic-hypoxic encephalopathy due to other systemic diseases. Cerebral edema can cause an increase in intracranial pressure in patients, which in turn can lead to a shift in brain tissue due to increased local pressure, and can even lead to brain herniation and life-threatening respiratory and cardiac arrest. In clinical practice, drugs such as mannitol, glycerol fructose sodium chloride injection and other hypertonic dehydrating agents or diuretics are usually used to reduce intracranial edema; local hypothermia or subhypnotic treatment can also be applied to reduce brain damage caused by edema. In addition, for patients with headache caused by increased intracranial pressure, the above methods can also be used to reduce the symptoms.