APPLICATION OF A 3-COMPARTMENT MODEL TO A STUDY OF THE EFFECTS OF SEX, ALCOHOL DOSE AND CONCENTRATION, EXERCISE AND FOOD-CONSUMPTION ON THE PHARMACOKINETICS OF ETHANOL IN HEALTHY-VOLUNTEERS

A recently developed three-compartment model for the absorption and elimination of ingested alcohol was applied to re-analyse a study on the effects of various factors known to influence the blood-alcohol curve. The absorption and elimination of alcohol after drinking diluted alcohol were studied in healthy volunteers under strictly standardized conditions. The factors studied were sex, dose, concentration, physical exercise, meal consumption before drinking, energy content and composition of the meal, and time of drinking in relation to meal consumption. Gastric emptying and absorption from the small intestine were assumed to be first-order, and a possible delay (or acceleration) of gastric emptying was accounted for by a feedback-control parameter. The elimination process was assumed to follow Michaelis-Menten kinetics. Clear effects were observed of sex and dose, and aspects of meal consumption on absorption and elimination of alcohol. The ingestion of a meal prior to the intake of alcohol reduced both the gastric emptying rate and absorption efficiency of alcohol. increased the gastric emptying delay and reduced the rate of elimination. The absorption efficiency was even lower when the alcohol was consumed during the meal instead of after the meal. Using alcohol during the meal accelerated gastric emptying and reduced absorption efficiency as well as rate of elimination. High-fat meals resulted in the highest gastric emptying rate and rate of absorption from the small intestine, whereas high-protein and high-sucrose meals resulted in the lowest gastric emptying rate. Simultaneous consumption of a high-sucrose meal and alcohol increased gastric emptying delay. The alcohol elimination rate was most enhanced by high-sucrose and high-carbohydrate meals. The model used provides insight into the processes of absorption and elimination of alcohol and thus has clear advantages over the interpretation of measures such as the peak-concentration or area under the blood-alcohol curve.