A 33-year-old homeless man is admitted to the hospital with hypothermia after police found him sleeping on a street corner during a snowstorm. Two days later, he becomes agitated and tremulous, and says that he sees bugs crawling on the wall. His temperature is 38.3°C (101°F), pulse is 100/min, and blood pressure is 180/90 mm Hg. Physical examination shows a mild intention tremor. He is oriented to person, but not to place or time. The physician orders an MRI of the brain, but the patient becomes uncooperative. Administration of which of the following is most appropriate at this time?
A) Amitriptyline
B) Chlorpromazine
C) Lithium carbonate
D) Lorazepam
E) Propofol