Fever, defined as temperature higher than 38.3C (100.9 F), is common in patients with head injuries and is associated with poor recovery after injury. The current standard of care is to use oral acetaminophen (Tylenol) followed by a body cooling device. This method can effectively reduce fever but results in a high rate of shivering. Shivering is stressful to the heart and can further worsen brain injury. Methods to combat shivering have been developed and are successful in limiting the stress in the majority of patients that use a body cooling device. However, the drugs used to control shivering are sedating and may also interfere with brain recovery.