title: Activities against Streptococcus pneumoniae of amoxicillin and cefotaxime at physiological concentrations: in vitro pharmacodynamic simulation.
abstract: An in vitro model simulating amoxicillin and cefotaxime concentrations in human serum (after standard doses) was used to explore the activities of these drugs over time against penicillin-susceptible and penicillin-resistant Streptococcus pneumoniae strains. An initial inoculum reduction percentage of > or = 90% was obtained with amoxicillin and maintained for 2 to 8 h, regardless of the strain tested. In contrast, experiments showed that cefotaxime had significantly (P < 0.001) less capability to reduce initial inocula of the penicillin-resistant pneumococci from 0.5 h on than amoxicillin, despite the same in vitro susceptibility to amoxicillin and cefotaxime in both strains.
authors.affiliation: Microbiology Department, School of Medicine, Universidad Complutense, Madrid, Spain.
authors.forename: I P
authors.initials: IP
authors.lastname: Balcabao
authors.forename: L
authors.initials: L
authors.lastname: Aguilar
authors.forename: M
authors.initials: M
authors.lastname: Martín
authors.forename: Y
authors.initials: Y
authors.lastname: García
authors.forename: R
authors.initials: R
authors.lastname: Dal-Ré
authors.forename: J
authors.initials: J
authors.lastname: Prieto
mesh_terms: D000658:Amoxicillin / Q000494:pharmacology*; D002439:Cefotaxime / Q000494:pharmacology*; D002511:Cephalosporins / Q000494:pharmacology*; D015169:Colony Count, Microbial; D010403:Penicillin Resistance; D010406:Penicillins / Q000494:pharmacology*; D013296:Streptococcus pneumoniae / Q000187:drug effects*
chemical_list: D002511:Cephalosporins; D010406:Penicillins; D000658:Amoxicillin; D002439:Cefotaxime