Ethanol as a selective inhibitor of microsomal barbiturate hydroxylation in vitro and in vivo.

Inhibition by ethanol of microsomal hydroxylation in vitro was studied for a series of barbiturates. Considerable variation was found both in the type and the degree of inhibition exerted by ethanol in this series. Degree of inhibition by ethanol, however, correlated well with both the increases in sleeping-time and the prolongation of half-life time of barbiturates found in rats acutely pretreated with a subnarcotic dose of ethanol. Results are interpreted to favour a distinct pharmacokinetic concept of barbiturate-ethanol interaction to occur in rats.