tokens: METHODS : Twenty - three dogs were randomized to receive either 1 ) three intravenous ( IV ) boluses of cocaine 7 . 5 mg / kg with ethanol ( 1 g / kg ) as an IV infusion ( C + E , n = 8 ) , 2 ) three cocaine boluses only ( C , n = 6 ) , 3 ) ethanol infusion only ( E , n = 5 ) , or 4 ) placebo boluses and infusion ( n = 4 ) .