Sulfadimethoxine Tablets
»Sulfadimethoxine Tablets contain not less than 90.0percent and not more than 110.0percent of the labeled amount of sulfadimethoxine (C12H14N4O4S).
Packaging and storage— Preserve in tight,light-resistant containers,and store at controlled room temperature.
Labeling— Label the Tablets to indicate that they are for veterinary use only.
Identification— Shake a quantity of finely powdered Tablets,equivalent to about 1g of sulfadimethoxine,with 5mLof diluted hydrochloric acid and 10mLof water.Filter,and to the filtrate add 2.5Nsodium hydroxide dropwise until a precipitate forms and redissolves.Add diluted hydrochloric acid dropwise until a precipitate forms.Collect the filtrate on a very fine filter,and wash it with water and with ether:the sulfadimethoxine so obtained meets the requirements for the Identificationtests under Sulfadimethoxine.
Uniformity of dosage units á905ñ: meet the requirements.
Assay—
Mobile phase,Standard preparation,and Chromatographic system— Proceed as directed in the Assayunder Sulfadimethoxine.
Assay preparation— Weigh and finely powder not fewer than 20Tablets.Transfer an accurately weighed portion of the powder,equivalent to about 50mg of sulfadimethoxine,to a 250-mLvolumetric flask,add about 200mLof Mobile phase,and swirl to dissolve.Dilute with Mobile phaseto volume,and mix.Filter if necessary to obtain a clear solution.Protect this solution from light.
Procedure— Proceed as directed in the Assayunder Sulfadimethoxine.Calculate the quantity,in mg,of sulfadimethoxine (C12H14N4O4S)in the portion of Tablets taken by the formula:
250C(rU/rS),
in which the terms are as defined therein.
Auxiliary Information— Staff Liaison:Ian DeVeau,Ph.D.,Senior Scientist
Expert Committee:(VET)Veterinary Drugs
USP28–NF23Page 1824
Pharmacopeial Forum:Volume No.27(2)Page 2198
Phone Number:1-301-816-8178