This article presents data on the relationship between the recent drinking histories of 80 healthy men aged 18 to 25 years and their intensities of reaction to challenges with 0.75 ml/kg of ethanol, 0.12 mg/kg of diazepam, and 0.20 mg/kg of diazepam. Significant and consistent negative correlations between the usual quantity x frequency of alcohol intake and scores on all 13 items of the Subjective High Assessment Scale were demonstrated. Expectation of the effects of alcohol appears to be an important mediator of these relationships, although other factors may be involved as well. Although few significant relationships were observed for more objective measures of reactions to the challenges, these data underscore the potential effect of drinking history on evaluations of subjective feelings following challenges with these drugs.