Packaging and storage— Preserve in tight containers.

Labeling— Label the Tablets to indicate that they are intended for veterinary use only.

USP Reference standards 11— USP Tetracycline Hydrochloride RS. USP Novobiocin RS.

Identification— Shake a suitable quantity of finely powdered Tablets with methanol to obtain a solution containing 1 mg of tetracycline hydrochloride per mL, and filter. Using the filtrate as the Test Solution, proceed as directed under Identification—Tetracyclines 193.

Disintegration 701: 60 minutes, simulated gastric fluid TS being substituted for water in the test.

Uniformity of dosage units 905: meet the requirements for Weight Variation with respect to tetracycline hydrochloride and to novobiocin sodium.

Loss on drying 731— Dry about 100 mg, accurately weighed, of finely powdered Tablets in a capillary-stoppered bottle in vacuum at a pressure not exceeding 5 mm of mercury at 60 for 3 hours: it loses not more than 6.0% of its weight.

Limit of 4-epianhydrotetracycline 226— To an accurately weighed quantity of finely powdered Tablets, equivalent to about 250 mg of tetracycline hydrochloride, add 10 mL of 0.1 N hydrochloric acid, and adjust with 6 N ammonium hydroxide to a pH of 7.8. Transfer this solution with the aid of EDTA Buffer to a 50-mL volumetric flask, dilute with EDTA Buffer to volume, and mix. Use this solution, without delay, as the Test Solution: not more than 2.0% is found.

Residual solvents 467: meet the requirements.

Assay for tetracycline hydrochloride— Proceed as directed for tetracycline under Antibiotics—Microbial Assays 81, except to use Escherichia coli ATCC 10536 as the test organism instead of Staphylococcus aureus ATCC 29737 and an inoculum composition of about 0.2 mL of stock suspension in each 100 mL of Medium 3. Transfer not less than 5 Tablets to a high-speed blender jar containing an accurately measured volume of 0.1 N hydrochloric acid, so that, after blending for about 3 to 5 minutes, the solution so obtained contains not less than 150 µg of tetracycline hydrochloride per mL. Dilute an accurately measured volume of this solution quantitatively and stepwise with water to obtain a Test Dilution having a concentration of tetracycline hydrochloride assumed to be equal to the median dose level of the Standard.

Assay for novobiocin— Proceed as directed for novobiocin under Antibiotics—Microbial Assays 81, blending not less than 5 Tablets for 3 to 5 minutes in a high-speed glass blender jar containing 1.0 mL of polysorbate 80 and a sufficient accurately measured volume of Buffer No. 3 to provide a stock solution of convenient concentration. Dilute an accurately measured volume of this stock solution quantitatively and stepwise with Buffer No. 6 to obtain a Test Dilution having a concentration of novobiocin assumed to be equal to the median dose level of the Standard.

Expert Committee : (VET05) Veterinary Drugs 05

USP29–NF24 Page 2104

Phone Number : 1-301-816-8178