Erythromycin Lactobionate for Injection
C37H67NO13.C12H22O12 1092.22

Erythromycin mono(4-O-b-D-galactopyranosyl-D-gluconate)(salt).
Erythromycin lactobionate (1:1)(salt) [3847-29-8].
»Erythromycin Lactobionate for Injection is a sterile,dry mixture of erythromycin lactobionate and a suitable preservative.It contains the equivalent of not less than 90.0percent and not more than 120.0percent of the labeled amount of erythromycin (C37H67NO13).
Packaging and storage— Preserve in Containers for Sterile Solidsas described under Injections á1ñ.
Constituted solution— At the time of use,it meets the requirements for Constituted Solutionsunder Injections á1ñ.
Identification,Infrared Absorption á197Mñ: the specimen and the Reference Standard being previously dried in vacuum at a pressure not exceeding 5mm of mercury at 60for 3hours.
Bacterial endotoxins á85ñ— It contains not more than 1.0USP Endotoxin Unit per mg of erythromycin.
pHá791ñ: between 6.5and 7.5,in a solution containing the equivalent of 50mg of erythromycin per mL.
Water,Method Iá921ñ: not more than 5.0%.
Particulate matter á788ñ: meets the requirements for small-volume injections when the constituted solution is diluted with filtered water to a concentration of not more than 5mg of erythromycin base per mLbefore the test is performed.
Other requirements— It meets the requirements under Injections á1ñ.
Assay— Proceed as directed for erythromycin under Antibiotics—Microbial Assays á81ñ,using Erythromycin Lactobionate for Injection constituted as directed in the labeling.Withdraw all of the withdrawable contents where the package is represented as being a single-dose container;or,where the labeling specifies the amount of erythromycin equivalent in a given volume of the resultant preparation,withdraw an accurately measured volume.Dilute quantitatively with water to obtain a stock solution containing the equivalent of about 10mg of erythromycin per mL.Dilute this stock solution quantitatively with Buffer No.3to obtain a Test Dilutionhaving a concentration assumed to be equal to the median dose level of the Standard.
Auxiliary Information— Staff Liaison:William W.Wright,Ph.D.,Scientific Fellow
Expert Committee:(PA7)Pharmaceutical Analysis 7
USP28–NF23Page 769
Phone Number:1-301-816-8335