title: Streptococcus pneumoniae killing rate and post-antibiotic effect of levofloxacin and ciprofloxacin.
abstract: In vitro killing rates for levofloxacin and ciprofloxacin for six strains of Streptococcus pneumoniae were determined by the time-kill method outlined by the NCCLS. Both drugs were bactericidal at concentrations of two and four times their respective minimum inhibitory concentrations (MICs). Levofloxacin achieved a 99.9% kill on average in 1 hour more rapidly than ciprofloxacin. Post-antibiotic effect was also determined for both drugs against the same six strains. A post-antibiotic effect for a mean of 1.2 and 1.0 hours was observed for levofloxacin and ciprofloxacin, respectively. The latter means were not considered significantly different.
authors.affiliation: The Clinical Microbiology Institute, Wilsonville, Oregon 97070, USA.
authors.forename: P C
authors.initials: PC
authors.lastname: Fuchs
authors.forename: A L
authors.initials: AL
authors.lastname: Barry
authors.forename: S D
authors.initials: SD
authors.lastname: Brown
mesh_terms: D000890:Anti-Infective Agents / Q000494:pharmacology*; D002939:Ciprofloxacin / Q000494:pharmacology*; D015169:Colony Count, Microbial; D064704:Levofloxacin; D008826:Microbial Sensitivity Tests; D015242:Ofloxacin / Q000494:pharmacology*; D013296:Streptococcus pneumoniae / Q000187:drug effects* / Q000235:genetics / Q000254:growth & development; D013997:Time Factors
chemical_list: D000890:Anti-Infective Agents; D002939:Ciprofloxacin; D064704:Levofloxacin; D015242:Ofloxacin