After intravenous bolus injections of 0.5, 1, and 2 g of cefotiam to three healthy volunteers, the mean (+/- standard deviation) total plasma clearances measured for each dose were, respectively, 26.8 +/- 2.7, 22.8 +/- 0.8, and 17.8 +/- 0.9 liters/h; the terminal elimination half-lives were 54.0 +/- 0.1, 68 +/- 15, and 98 +/- 36 min; and the renal clearances were 16.0 +/- 2.9, 13.3 +/- 1.4, and 11.3 +/- 2.6 liters/h. The 24-h urinary recovery was independent of the dose and averaged 53% of the dose. After intramuscular administration of 1 g of cefotiam to three healthy volunteers, a mean (+/- standard deviation) peak concentration of 16.6 +/- 5.1 micrograms/ml was reached at 0.75 to 1 h post dosing. The concurrent intramuscular administration of lidocaine and cefotiam did not modify the kinetics of cefotiam. During a constant-rate infusion, the steady-state plasma clearance decreased slightly when the infusion rate was increased. There was no trend towards accumulation of cefotiam in plasma during chronic treatment with 1 g intravenously every 12 h for 10 days.