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°C for 6 months.
Antibiotic solutions were prepared with aseptic techniques by reconstitution and dilution of the commercially available powders (amikacin, ceftazidime, and vancomycin) and stored at −20°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.
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°C for 190 days. A time limitation of 6 months is proposed.
Fortified ophthalmic antibiotic solutions prepared and supplied by a pharmacy can be stored in freezers at −20°C for later use.
From the Departments of *Pharmacy; †Microbiology; ‡Pharmacology; and §Ophthalmology; University Hospital of Caen, Caen, France.
Received for publication February 26, 2009; revision received September 16, 2009; accepted September 23, 2009.
Presented partially at the Association for Research in Vision and Ophthalmology Annual Meeting, May 3-7, 2009, Fort Lauderdale, FL.
Competing interests: none.
Reprints: Frédéric Mouriaux, Ophthalmology Department, University Hospital of Caen, 14032 Caen Cedex, Caen, France (e-mail: firstname.lastname@example.org).