title: Comparative in vitro study of the antimicrobial activities of different commercial antibiotic products for intravenous administration.
abstract: BACKGROUND
  The antimicrobial resistance is a global problem, probably due to the indiscriminate and irrational use of antibiotics, prescriptions for incorrect medicines or incorrect determinations of dose, route and/or duration. Another consideration is the uncertainty of patients receiving antibiotics about whether the quality of a generic medicine is equal to, greater than or less than its equivalent brand-name drug. The antibiotics behaviors must be evaluated in vitro and in vivo in order to confirm their suitability for therapeutic use.
  
  
  METHODS
  The antimicrobial activities of Meropenem and Piperacillin/Tazobactam were studied by microbiological assays to determine their potencies (content), minimal inhibitory concentrations (MICs), critical concentrations and capacity to produce spontaneous drug-resistant mutants.
  
  
  RESULTS
  With respect to potency (content) all the products fulfill USP requirements, so they should all be considered pharmaceutical equivalents. The MIC values of the samples evaluated (trade marks and generics) were the same for each strain tested, indicating that all products behaved similarly. The critical concentration values were very similar for all samples, and the ratios between the critical concentration of the standard and those of each sample were similar to the ratios of their specific antibiotic contents. Overall, therefore, the results showed no significant differences among samples. Finally, the production of spontaneous mutants did not differ significantly among the samples evaluated.
  
  
  CONCLUSIONS
  All the samples are pharmaceutical equivalents and the products can be used in antimicrobial therapy.
authors.affiliation: UNIVERSIDAD NACIONAL DE COLOMBIA, FACULTAD DE CIENCIAS, DEPARTAMENTO DE FARMACIA, Laboratorio de Asesorías e Investigaciones en Microbiología. Postal Code: 472. Ciudad Universitaria. Carrera 30 Calle 45. A.A. 14490, Bogotá D. C., Colombia.
authors.forename: Edelberto
authors.initials: E
authors.lastname: Silva
authors.affiliation: UNIVERSIDAD NACIONAL DE COLOMBIA, FACULTAD DE CIENCIAS, DEPARTAMENTO DE FARMACIA, Laboratorio de Asesorías e Investigaciones en Microbiología. Postal Code: 472. Ciudad Universitaria. Carrera 30 Calle 45. A.A. 14490, Bogotá D. C., Colombia.
authors.forename: Jorge A
authors.initials: JA
authors.lastname: Díaz
authors.affiliation: UNIVERSIDAD NACIONAL DE COLOMBIA, FACULTAD DE CIENCIAS, DEPARTAMENTO DE FARMACIA, Laboratorio de Asesorías e Investigaciones en Microbiología. Postal Code: 472. Ciudad Universitaria. Carrera 30 Calle 45. A.A. 14490, Bogotá D. C., Colombia.
authors.forename: María J
authors.initials: MJ
authors.lastname: Arias
authors.affiliation: UNIVERSIDAD NACIONAL DE COLOMBIA, FACULTAD DE CIENCIAS, DEPARTAMENTO DE FARMACIA, Laboratorio de Asesorías e Investigaciones en Microbiología. Postal Code: 472. Ciudad Universitaria. Carrera 30 Calle 45. A.A. 14490, Bogotá D. C., Colombia.
authors.forename: Angela P
authors.initials: AP
authors.lastname: Hernández
authors.affiliation: UNIVERSIDAD NACIONAL DE COLOMBIA, FACULTAD DE CIENCIAS, DEPARTAMENTO DE FARMACIA, Laboratorio de Asesorías e Investigaciones en Microbiología. Postal Code: 472. Ciudad Universitaria. Carrera 30 Calle 45. A.A. 14490, Bogotá D. C., Colombia.
authors.forename: Andrés
authors.initials: A
authors.lastname: de la Torre
mesh_terms: D000818:Animals; D000900:Anti-Bacterial Agents / Q000494:pharmacology* / Q000627:therapeutic use; D001419:Bacteria / Q000187:drug effects*; D002169:Campylobacter Infections / Q000188:drug therapy / Q000378:metabolism; D004351:Drug Resistance / Q000187:drug effects / Q000235:genetics; D024901:Drug Resistance, Multiple, Bacterial / Q000235:genetics; D006801:Humans; D007262:Infusions, Intravenous; D007275:Injections, Intravenous; D000077731:Meropenem; D051379:Mice; D008807:Mice, Inbred BALB C; D010397:Penicillanic Acid / Q000031:analogs & derivatives / Q000494:pharmacology / Q000627:therapeutic use; D010878:Piperacillin / Q000494:pharmacology / Q000627:therapeutic use; D000078142:Tazobactam; D013845:Thienamycins / Q000494:pharmacology / Q000627:therapeutic use; D014018:Tissue Distribution; D065093:beta-Lactamase Inhibitors
chemical_list: D000900:Anti-Bacterial Agents; D013845:Thienamycins; D065093:beta-Lactamase Inhibitors; D010397:Penicillanic Acid; D000077731:Meropenem; D000078142:Tazobactam; D010878:Piperacillin