Cimetidine Injection
»Cimetidine Injection is a sterile solution of Cimetidine Hydrochloride in Water for Injection.It contains not less than 90.0percent and not more than 110.0percent of the labeled amount of C10H16N6S.
Packaging and storage— Preserve in single-dose or multiple-dose glass or plastic containers.Glass containers are preferably of Type Ior Type IIglass.
Identification— The chromatogram of the Assay preparationexhibits a major peak for cimetidine,the retention time of which corresponds to that of the cimetidine peak in the chromatogram of the Standard preparation,as obtained in the Assay.
Bacterial endotoxins á85ñ— It contains not more than 0.5USP Endotoxin Unit per mg of cimetidine hydrochloride.
pHá791ñ: between 3.8and 6.0.
Other requirements— It meets the requirements under Injections á1ñ.
Assay—
Mobile phase,Standard preparation,andChromatographic system— Proceed as directed in the Assayunder Cimetidine Hydrochloride.
Assay preparation— Transfer an accurately measured volume of Injection,equivalent to about 2mg of cimetidine,to a 200-mLvolumetric flask,dilute with Mobile phaseto volume,and mix.
Procedure— Separately inject equal volumes (about 50µL)of the Standard preparationand the Assay preparationinto the chromatograph,record the chromatograms,and measure the peak responses.Calculate the quantity,in mg,of C10H16N6Sin each mLof the Injection taken by the formula:
200(252.34/288.81)(C/V)(rU/rS),
in which 252.34and 288.81are the molecular weights of cimetidine and cimetidine hydrochloride,respectively;Cis the concentration,in mg per mL,of USP Cimetidine Hydrochloride RSin the Standard preparation;Vis the volume of Injection taken;and rUand rSare the cimetidine peak responses obtained from the Assay preparationand the Standard preparation,respectively.
Auxiliary Information— Staff Liaison:Elena Gonikberg,Ph.D.,Scientist
Expert Committee:(PA4)Pharmaceutical Analysis 4
USP28–NF23Page 474
Phone Number:1-301-816-8251