Intracranial infection is indicated when symptoms such as fever, headache, and cervical tonicity occur 2 to 3 days after craniotomy or open cranial injury, and when routine biochemical tests of cerebrospinal fluid detect abnormal pathogenic microorganisms in the skull. One of the necessary tests to confirm the diagnosis of intracranial infection is a cerebrospinal fluid examination, which is usually done by lumbar puncture (sometimes direct ventriculocentesis is possible) to extract a small amount of cerebrospinal fluid. The usual findings are an increase in cerebrospinal fluid leukocytes, which can range from a few hundred to tens of thousands, an increase in the cerebrospinal fluid neutrophil ratio, an increase in the leukocyte/total cell ratio; an increase in cerebrospinal fluid protein and a decrease in cerebrospinal fluid sugar; and, a culture of the pathogen, which, when combined with the biochemical findings, can confirm the diagnosis of an intracranial infection. If conditions allow, this can be combined with a cranial enhancement MRI or CT to look inside the brain and to see if there is a pathogen causing brain abscess formation. If an intracranial infection is detected, and if the infection is not treated properly and is not effectively controlled, the condition will soon worsen or even die. If proper treatment is adhered to in a timely manner, the majority of patients can be cured of intracranial infections without leaving sequelae. So what is the correct treatment? Generally speaking, if it is an intracranial bacterial infection, antibiotics should be used routinely. ◆Mild intracranial infections can be controlled by antibiotics with a suspension. However, because the brain tissue is not directly connected to the blood circulation system, but through a structure called blood-brain barrier to exchange substances, so at this time, we should pay attention to choose antibiotics that can easily pass the blood-brain barrier for treatment; otherwise, if the antibiotics enter from the systemic veins, it is also difficult to control the infection if the concentration of antibiotics reaching the brain lesion is not enough. Common drugs are, meropenem, vancomycin, ceftazidime, amikacin, etc. ◆If it is a serious intracranial infection, local medication is usually needed to achieve precise treatment. Unlike the systemic use of antibiotics to control intracranial infections, the precise use of drugs at this time, directly acting on the foci of infection in the brain, while increasing the concentration of drugs in local foci, reducing drug damage to liver and kidney functions and other side effects, we should use drugs with better local effects as far as possible, such as meropenem, vancomycin, etc. Although sometimes the drug sensitivity shows drug resistance, but because of the high local concentration, it can also have a good effect. It can also have a good effect. Cefoperazone, polymyxin, tigecycline, etc. are not recommended because they cannot cross the blood-brain barrier, although they are sometimes sensitive. There are many benefits of such medication: small total amount of medication, low cost, few systemic side effects, and high cure rate. For serious intracranial infections, and when the pathogenic microorganisms are particularly resistant, in turn, it is not recommended that multiple antibiotics be used in large quantities or even in excessive doses systemically, which not only cannot eradicate the infected lesions, but also lead to damage to liver and kidney functions and the gastrointestinal tract. After a period of anti-infection treatment, if the patient’s temperature returns to normal, the headache and cervical ankylosis disappear, and the biochemical examination of the cerebrospinal fluid shows that the indicators of the cerebrospinal fluid have gradually recovered, it is necessary to draw the cerebrospinal fluid two to three times in a row, and the test results are all consistent before the intracranial infection is completely cured. (Note that even if the cerebrospinal fluid is negative for pathogens, it is not necessarily cured if the cerebrospinal fluid leukocytes are elevated and the cerebrospinal fluid sugar is decreased.) Finally, intracranial infection is not terrible, what is terrible is the delay, and all kinds of wrong treatment, delaying the best time for treatment!