Packaging and storage—
Preserve in multiple-dose containers.
Labeling—
Label it to indicate that it is for veterinary use only. Label it to state that it is for intramuscular administration only.
Identification—
Transfer a quantity of Injection, equivalent to about 5 mg of erythromycin, to a separator containing 50 mL of solvent hexane. Shake until dissolved. Extract with three separate 20-mL portions of methanol. Combine the methanol extracts in a beaker, and evaporate to dryness. Dissolve the residue in 2 mL of methanol (test solution). Proceed as directed in the
Identification test under
Erythromycin Delayed-Release Capsules, beginning with “Prepare a Standard solution of
USP Erythromycin RS.”
Water, Method I 
921
:
not more than 1.0%, 20 mL of a mixture of toluene and methanol (7:3) being used in place of methanol in the titration vessel.
Sterility 71—
It meets the requirements when tested as directed for
Direct Inoculation of the Culture Medium under
Test for Sterility of the Product to be Examined.
Other requirements—
It meets the requirements under
Injections 1.
Assay—
Transfer an accurately measured volume of Injection, equivalent to about 50 mg of erythromycin, to a separator containing 50 mL of solvent hexane. Shake until dissolved. Wash with four separate 20-mL portions of a mixture of methanol and water (4:1). Combine the washings in a 100-mL volumetric flask, dilute with the methanol and water solution to volume, and mix. Proceed as directed for erythromycin under
Antibiotics—Microbial Assays 81, using an accurately measured volume of this stock solution diluted quantitatively with
Buffer No. 3 to yield a
Test Dilution having a concentration of erythromycin assumed to be equal to the median dose level of the Standard.
