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Sulfadimethoxine Oral Suspension
» Sulfadimethoxine Oral Suspension contains not less than 90.0 percent and not more than 110.0 percent of the labeled amount of sulfadimethoxine (C12H14N4O4S).
Packaging and storage— Preserve in tight, light-resistant containers, and store at controlled room temperature.
Labeling— Label it to indicate that it is for veterinary use only.
Identification— Shake a quantity equivalent to about 50 mg with 50 mL of water, and add 2.5 N sodium hydroxide dropwise until the solution becomes clear. Add diluted hydrochloric acid dropwise until a precipitate forms. Collect the precipitate on a very fine filter, and wash it with water and with ether: the sulfadimethoxine so obtained meets the requirements for the Identification tests under Sulfadimethoxine.
pH 791: between 5.0 and 7.0.
Residual solvents 467: meets the requirements.
(Official January 1, 2007)
Assay—
Mobile phase, Standard preparation, and Chromatographic system— Proceed as directed in the Assay under Sulfadimethoxine.
Assay preparation— Transfer an accurately measured volume of Suspension, previously mixed and free from air bubbles, equivalent to about 50 mg of sulfadimethoxine, to a 250-mL volumetric flask, add about 200 mL of Mobile phase, and swirl to dissolve. Dilute with Mobile phase to volume, and mix. Protect this solution from light.
Procedure— Proceed as directed in the Assay under Sulfadimethoxine. Calculate the quantity, in mg, of sulfadimethoxine (C12H14N4O4S) in each mL of the Oral Suspension taken by the formula:
250(C/V)(rU / rS),
in which V is the volume, in mL, of Oral Suspension taken to prepare the Assay preparation; and the other terms are as defined therein.
Auxiliary Information— Staff Liaison : Ian DeVeau, Ph.D., Associate Director
Expert Committee : (VET05) Veterinary Drugs 05
USP29–NF24 Page 2028
Pharmacopeial Forum : Volume No. 27(2) Page 2198
Phone Number : 1-301-816-8178