Comparative trial in volunteers to investigate possible ethanol-ranitidine interaction

To assess the effect of ranitidine on ethanol absorption after ethanol 0.5 g/kg is given in three single doses of 0.167 g/kg to simulate normal social drinking.

A double-blind, placebo-controlled, crossover trial was performed in 16 healthy men. Ethanol serum concentrations were measured on day 6 of each of the three treatment periods (placebo, ranitidine 150 mg bid, or ranitidine 300 mg bid).

Ethanol 0.167 g/kg was administered followed by a standard meal at 1700. The last tablet of the test medication was given 15 minutes later. Thirty and 60 minutes after the first intake, the same amount of ethanol was given again. Serum ethanol concentrations were measured multiple times during the four-hour period following oral ingestion of the first dose.

Comparison of median serum ethanol concentrations, the areas under the curve, peak and time to peak serum ethanol concentrations showed no significant differences during medication with placebo, ranitidine 150 mg bid, or ranitidine 300 mg bid. Peak ethanol concentrations (median values) were 153, 140, and 155 mg/L, respectively.

This study shows that treatment with ranitidine, in a dose up to 300 mg bid, has no significant effect on serum ethanol concentrations, even when ethanol was given in divided doses to simulate normal patterns of social drinking. This implies that concomitant dosing with ranitidine will not increase the adverse effects of moderate doses of ethanol on concentration and psychomotor function.