title: In vitro stability of fortified ophthalmic antibiotics stored at -20 degrees C for 6 months.
abstract: OBJECTIVE
  This study evaluates the in vitro stability and sterility of fortified ophthalmic antibiotic preparations of 5% solutions (50 mg/mL) made from commercially available powders of amikacin, ceftazidime, and vancomycin stored at -20 degrees C for 6 months.
  
  
  METHODS
  Antibiotic solutions were prepared with aseptic techniques by reconstitution and dilution of the commercially available powders (amikacin, ceftazidime, and vancomycin) and stored at -20 degrees C. After various durations of storage, the stability of various physical and chemical properties was determined by a pH meter, an osmometer, and high-performance liquid chromatography. Microbiological activity was assayed according to the European Pharmacopoeia.
  
  
  RESULTS
  Solutions of 5% amikacin or ceftazidime in 0.9% sodium chloride and vancomycin in 5% dextrose were found to be physically, chemically, and microbiologically stable after storage at -20 degrees C for 190 days. A time limitation of 6 months is proposed.
  
  
  CONCLUSIONS
  Fortified ophthalmic antibiotic solutions prepared and supplied by a pharmacy can be stored in freezers at -20 degrees C for later use.
authors.affiliation: Department of Pharmacy, University Hospital of Caen, Caen, France.
authors.forename: Valérie
authors.initials: V
authors.lastname: Chédru-Legros
authors.forename: Marguerite
authors.initials: M
authors.lastname: Fines-Guyon
authors.forename: Aurélie
authors.initials: A
authors.lastname: Chérel
authors.forename: Agathe
authors.initials: A
authors.lastname: Perdriel
authors.forename: Françoise
authors.initials: F
authors.lastname: Albessard
authors.forename: Danièle
authors.initials: D
authors.lastname: Debruyne
authors.forename: Frédéric
authors.initials: F
authors.lastname: Mouriaux
mesh_terms: D000583:Amikacin / Q000737:chemistry; D000900:Anti-Bacterial Agents / Q000737:chemistry*; D002442:Ceftazidime / Q000737:chemistry; D015925:Cryopreservation; D004355:Drug Stability; D004356:Drug Storage; D008826:Microbial Sensitivity Tests; D009883:Ophthalmic Solutions / Q000737:chemistry*; D013997:Time Factors; D014640:Vancomycin / Q000737:chemistry
chemical_list: D000900:Anti-Bacterial Agents; D009883:Ophthalmic Solutions; D014640:Vancomycin; D000583:Amikacin; D002442:Ceftazidime