In naive animals the rate of ethanol elimination is dependent on the hepatic alcohol dehydrogenase activity. Carbohydrates have been shown to modify ethanol metabolism by a mechanism that has not been determined. In this study, adult female rats, fed chow diets supplemented with fructose or glucose in their drinking water for 10 days demonstrated significantly greater ethanol elimination rates (4.85 +/- 0.28 and 4.92 +/- 1.56 microM ethanol/min/g liver, respectively) than rats receiving water (3.65 +/- 0.29). The hepatic alcohol dehydrogenase activity of the fructose (1687 +/- 101 nM ethanol/min/g liver) and the glucose (1832 +/- 15)-supplemented rats were not significantly different from that of control rats (1845 +/- 160). Dietary carbohydrate supplementation, therefore, enhanced ethanol elimination, but did not alter the activity of alcohol dehydrogenase. Thus the changes in the ethanol elimination rate following carbohydrate loading were not the consequence of an alteration in hepatic alcohol dehydrogenase.