Neurocritical patients who can self-report pain use the 0-10 numerical rating scale (NRS, verbal or visual form). However, critically ill patients whose nervous systems cannot express pain use the behavioral pain scale (BPS) and the critical care pain observation tool (CPOT) behavioral pain assessment tools. These tools reveal pain-related changes in movement, facial expression, posture, and physiological indicators such as heart rate, blood pressure, and respiratory rate. In pain control, it is first essential to reduce unnecessary painkillers through non-drug therapy and maximize the effect of the administered analgesics. For nonneuropathic pain, narcotic analgesics such as fentanyl, hydromorphone, morphine, and remifentanil are administered intravenously. Gabapentin, pregabalin, and carbamazepine are recommended along with narcotic analgesics for neuropathic pain control. In addition, nonnarcotic analgesics for multi-modal analgesia are used to reduce the use of narcotic analgesics or the side effects of narcotic analgesics. In the intensive care unit (ICU), the sedation-agitation scale (SAS) and the Richmond agitation-sedation scale (RASS) are used to determine the depth of sedation to be maintained during shallow or deep sedation, considering the condition of the critically ill patient. When selecting sedatives for critically ill patients, preferentially consider nonbenzodiazepines such as propofol or dexmedetomidine rather than benzodiazepines such as midazolam or lorazepam. In addition, patients use painkillers or sedatives for over a week, and neurological changes or physiological dependence may occur. Therefore, clinicians should evaluate the critically ill patient’s condition, and sedatives and painkillers should be reduced or discontinued.