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 1 g of sulfadimethoxine, with 5 mL of diluted hydrochloric acid and 10 mL of water. Filter, and to the filtrate add 2.5 N sodium 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
Identification tests under
Sulfadimethoxine.
Assay—
Mobile phase, Standard preparation, and Chromatographic system—
Proceed as directed in the
Assay under
Sulfadimethoxine.
Assay preparation—
Weigh and finely powder not fewer than 20 Tablets. Transfer an accurately weighed portion of the powder, 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. Filter if necessary to obtain a clear solution. Protect this solution from light.
Procedure—
Proceed as directed in the
Assay under
Sulfadimethoxine. Calculate the quantity, in mg, of sulfadimethoxine (C
12H
14N
4O
4S) 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., Associate Director
Expert Committee : (VET05) Veterinary Drugs 05
USP29–NF24 Page 2029
Pharmacopeial Forum : Volume No. 27(2) Page 2198
Phone Number : 1-301-816-8178
701
:
30 minutes.