The pharmacokinetics of cefotiam were studied after a single intravenous 1.0-g dose to 18 subjects grouped according to their creatinine clearances (CLCR); CLCR was above 75, 75 to 20, and below 20 ml/min per 1.73 m2 in groups 1, 2, and 3, respectively. Cefotiam obeyed two-compartment model kinetics in all three groups. The volume of distribution based on the area under serum concentration-time curve (Varea) was renal function independent, the average value being 0.350 +/- 0.159 liters/kg. The elimination-phase half-life (t1/2 beta) was 0.916 +/- 0.090 h in group 1, 2.03 +/- 1.62 h in group 2, and 7.09 +/- 3.06 h in group 3. Cumulative 24-h urinary excretion accounted for 65 to 93% of the dose in four subjects with CLCRS above 80 ml/min per 1.73 m2 and 19 to 41% in three subjects with CLCRS below 20 ml/min per 1.73 m2. We give recommendations for dosage adjustment in patients with renal insufficiency. The effect of hemodialysis on cefotiam pharmacokinetics was studied in six patients in end-stage renal failure; hemodialysis shortened the average t1/2 beta from 8.02 +/- 4.04 h to 2.74 +/- 2.15 h. We estimated that in a hypothetical anephric patient with a body weight of 60 kg, 6-h hemodialysis would remove 49.7% of the drug present in the body at the start of dialysis.