A 27-year-old, previously healthy man suddenly collapses at a party where both legal and illicit drugs are being used. En route to the hospital, he requires resuscitation with defibrillation to establish a normal cardiac rhythm. On physical examination, his temperature is 40deg C; respirations, 30/ min; heart rate, 110/min; and blood pressure, 175/90 mm Hg. He has dilated pupils, a perforated nasal septum, and a prominent callus on the right thumb. CT scan of the head shows an acute right frontal lobe hemorrhage. Which of the following substances is most likely responsible for these findings?
Amphetamine Barbiturate Cocaine Ethanol