Are alcohol and glucose blood levels modified in fasting subjects taking ranitidine? This experience tries to simulate normal life conditions. Nine men, volunteer, aged from 24 to 29 years old, without any digestive symptoms, ate a standard lunch and after five hours of fasting, took 0.35 g of alcohol per kg. Ethanol blood levels, glycemia and blood levels of insulin and glucagon were taken at regular intervals every 10 to 15 minutes during all the experiment (120 minutes). After the initial experiment, all subjects took 150 mg of ranitidine p.o. b.i.d. during seven days. Afterward they were submitted to the same protocol. Between both experiments no differences were found on blood levels of ethanol. Peak concentration, decreasing rate, and biodisponibility (estimated by area under the curve) did not change. There was a tendency to have a faster decrease in glucose blood level (p < 0.05). This study does not show any significant modification of ethanol metabolism after taking ranitidine p.o.; those results are differing from data already found with studies using cimetidine.