title: Pharmacokinetic profile of levofloxacin following once-daily 500-milligram oral or intravenous doses.
abstract: The pharmacokinetics of once-daily oral levofloxacin (study A) or intravenous levofloxacin (study B) in 40 healthy male volunteers were investigated in two separate randomized, double-blind, parallel-design, placebo-controlled studies. Levofloxacin at 500 mg or placebo was administered orally or intravenously as a single dose on day 1; daily oral or intravenous dosing resumed on days 4 to 10. In a third study (study C), the comparability of the bioavailabilities of two oral and one intravenous levofloxacin formulations were investigated with 24 healthy male subjects in an open-label, randomized, three-way crossover study. Levofloxacin at 500 mg as a single tablet or an intravenous infusion was administered on day 1; following a 1-week washout period, subjects received the second regimen (i.e., the other oral formulation or the intravenous infusion); the third and final regimen was administered following a 1-week washout period. The concentrations of drug in plasma and urine were measured by validated high-pressure liquid chromatography methods. Pharmacokinetic parameters were estimated by noncompartmental methods. In both study A (oral levofloxacin) and study B (intravenous levofloxacin), steady state was attained within 48 h after the start of the multiple dosing on day 4. Levofloxacin pharmacokinetics were linear and predictable for the single and multiple 500-mg, once-daily oral and intravenous dosing regimens, and the values of the pharmacokinetic parameters for the oral and intravenous administrations were similar. Study C indicated that levofloxacin was rapidly and completely absorbed from the oral tablets, with mean times to the maximum concentration of drug in serum of approximately 1.5 h and mean absolute bioavailability of > or =99%. These results support the interchangeability of the oral and intravenous routes of levofloxacin administration.
authors.affiliation: The R.W. Johnson Pharmaceutical Research Institute, Raritan, New Jersey 08869, USA.
authors.forename: S C
authors.initials: SC
authors.lastname: Chien
authors.forename: M C
authors.initials: MC
authors.lastname: Rogge
authors.forename: L G
authors.initials: LG
authors.lastname: Gisclon
authors.forename: C
authors.initials: C
authors.lastname: Curtin
authors.forename: F
authors.initials: F
authors.lastname: Wong
authors.forename: J
authors.initials: J
authors.lastname: Natarajan
authors.forename: R R
authors.initials: RR
authors.lastname: Williams
authors.forename: C L
authors.initials: CL
authors.lastname: Fowler
authors.forename: W K
authors.initials: WK
authors.lastname: Cheung
authors.forename: A T
authors.initials: AT
authors.lastname: Chow
mesh_terms: D000284:Administration, Oral; D000293:Adolescent; D000328:Adult; D000890:Anti-Infective Agents / Q000008:administration & dosage / Q000009:adverse effects / Q000493:pharmacokinetics*; D019540:Area Under Curve; D001682:Biological Availability; D002851:Chromatography, High Pressure Liquid; D004311:Double-Blind Method; D006207:Half-Life; D006801:Humans; D007275:Injections, Intravenous; D064704:Levofloxacin; D008297:Male; D008875:Middle Aged; D015242:Ofloxacin / Q000008:administration & dosage / Q000009:adverse effects / Q000493:pharmacokinetics*; D013056:Spectrophotometry, Ultraviolet
chemical_list: D000890:Anti-Infective Agents; D064704:Levofloxacin; D015242:Ofloxacin