Ethanol and pentobarbital: comparison of behavioral and subjective effects in sedative drug abusers.

The behavioral and subjective effects of acute oral doses of placebo, ethanol (0.5, 1.0, and 2.0 g/kg), and pentobarbital (150, 300, 600, and 750 mg/70 kg) were compared in 8 male volunteers with histories of sedative drug abuse using a double-blind, double-dummy, cross-over design. Ethanol and pentobarbital produced similar dose-related decrements in psychomotor and cognitive performance and exhibited a similar profile of effects on staff- and participant-rated measures. There was some evidence indicating that, at the highest dose, pentobarbital was perceived by participants as being more sedating than ethanol and that pentobarbital has a greater abuse liability than ethanol. In conjunction with the results of previous human laboratory studies comparing the effects of different types of sedative-hypnotic drugs, these results support a mostly barbiturate-like rather than benzodiazepine-like profile of effects for ethanol.