Cefoxitin Injection
»Cefoxitin Injection is a sterile solution of Cefoxitin Sodium and one or more suitable buffer substances in Water for Injection.It contains Dextrose or Sodium Chloride as a tonicity-adjusting agent.It contains the equivalent of not less than 90.0percent and not more than 120.0percent of the labeled amount of cefoxitin (C16H17N3O7S2).
Packaging and storage— Preserve in Containers for Injectionsas described under Injections á1ñ.Maintain in the frozen state.
Labeling— It meets the requirements for Labelingunder Injections á1ñ.The label states that it is to be thawed just prior to use,describes conditions for proper storage of the resultant solution,and directs that the solution is not to be refrozen.
Identification— The chromatogram of the Assay preparationobtained as directed in the Assayexhibits a major peak for cefoxitin,the retention time of which corresponds to that exhibited in the chromatogram of the Standard preparationobtained as directed in the Assay.
Bacterial endotoxins á85ñ— It contains not more than 0.13USP Endotoxin Unit per mg of cefoxitin.
Sterility á71ñ— It meets the requirements when tested as directed for Membrane Filtrationunder Test for Sterility of the Product to be Examined.
pHá791ñ: between 4.5and 8.0.
Particulate matter á788ñ: meets the requirements for small-volume injections.
Assay—
Mobile phase ,Phosphate buffer,Standard preparation,and Chromatographic system—Prepare as directed in the Assayunder Cefoxitin Sodium.
Assay preparation— Allow 1container of Injection to thaw,and mix.Dilute an accurately measured volume of Injection quantitatively with Phosphate bufferto obtain a solution containing about 0.3mg of cefoxitin per mL.Use this solution within 5hours.
Procedure— Proceed as directed in the Assayunder Cefoxitin Sodium.Calculate the quantity,in mg,of cefoxitin (C16H17N3O7S2)in each mLof the Injection taken by the formula:
(CP/1000)(L/D)(rU/rS),
in which Lis the labeled quantity,in mg,of cefoxitin (C16H17N3O7S2)in each mLof Injection taken,Dis the concentration,in mg per mL,of the Assay preparation,based on the volume of Injection taken and the extent of dilution,and the other terms are as defined therein.
Auxiliary Information— Staff Liaison:William W.Wright,Ph.D.,Scientific Fellow
Expert Committee:(PA7)Pharmaceutical Analysis 7
USP28–NF23Page 395
Phone Number:1-301-816-8335