Pharmacokinetics of multiple intravenous instillation of levofloxacin in Chinese healthy subjects.

AIM: To study the pharmacokinetics of multiple doses intravenous infusion of
levofloxacin instillation in Chinese healthy volunteers.
METHODS: Intravenous infusion of levofloxacin instillation 200 mg within 60 min
was given to 10 male healthy volunteers for 7 d, on d 1 and d 7, once-daily, from
2-6 d twice-daily dosing. The concentrations of levofloxacin in serum and urine
were assayed by HPLC.
RESULTS: The main pharmacokinetic parameters af ter the first dosing were as
follows: Cmax was (2.4+/-0.4) mg/L; AUC0- was (16.1 +/- 1.4) mg . h . L-1;
T1/2beta was (6.3 +/- 0.3) h. The concentration in serum reached steady state
within 72 h. The main parameters after the last dosing were as follows: Cssmax
was (2.9 +/- 0.4) mg/L; Cssmin was (0.71 +/- 0.19) mg/L; Cav was (1.40 +/- 0.29)
mg/L; AUCss0-12 was (17 +/- 3) mg . h . L-1; T1/2beta was (6.2 +/- 0.8) h. The
24-h cumulative urinary excretion rate was (88 +/- 5) %. From the calculation,
the cumulative rate was 1.20; the fluctuation index was 1.30. The difference of
T1/2beta and AUC between the first dosing and the last dosing was not
significant, and the elimination rate of levofloxacin was not changed after
multiple dosing. No clear adverse events were noted during this study.
CONCLUSION: There was no accumulation of drug after the repeated intravenous
infusion with 200 mg levofloxacin instillation for 7 d.