A physiological model of ampicillin pharmacokinetics in man is proposed. Its design stems from the data characterizing the antibiotic distribution in rats. The model is useful in describing the pharmacokinetics of ampicillin after its intravenous and intramuscular administration. An adequate description of the antibiotic distribution in blood suggested an agreement with the real values of the estimated antibiotic concentrations in the tissues. The concentrations of ampicillin and sulbactam in the tissues after their intramuscular combined administration in doses of 1 and 0.5 g, respectively, were compared. The physiological model of the pharmacokinetics was applied to evaluation of a possible interval in changing of the antibiotic half-life. There was analytical relationship between the ampicillin half-life and efficiency of the renal function.
