Methenamine Mandelate Tablets
» Methenamine Mandelate Tablets contain not less than 95.0 percent and not more than 105.0 percent of the labeled amount of methenamine mandelate (C6H12N4·C8H8O3).
Packaging and storage— Preserve in well-closed containers.
USP Reference standards 11
USP Methenamine Mandelate RS Click to View Structure
Identification, Infrared Absorption 197 Obtain the test specimen as follows. Triturate a quantity of finely powdered Tablets, equivalent to about 5.0 mg of methenamine mandelate, with 5 mL of chloroform, and pass through a 0.45-µm membrane filter. Evaporate the solvent, and allow the residue to air-dry.
Dissolution 711
for uncoated or plain coated tablets
Medium: water; 900 mL.
Apparatus 1: 100 rpm.
Time: 45 minutes.
Procedure— Determine the amount of C6H12N4·C8H8O3 dissolved from UV absorbances at the wavelength of maximum absorbance at about 257 nm of portions of the solution under test, filtered through a 0.45-µm filter and suitably diluted with Medium, if necessary, in comparison with a Standard solution having a known concentration of USP Methenamine Mandelate RS in the same Medium.
Tolerances— Not less than 75% (Q) of the labeled amount of C6H12N4·C8H8O3 is dissolved in 45 minutes.
Uniformity of dosage units 905: meet the requirements.
Assay— Weigh and finely powder not fewer than 20 Tablets. Weigh accurately a portion of the powder, equivalent to about 60 mg of methenamine mandelate, and transfer to a 250-mL conical flask. Proceed as directed in the Assay under Methenamine Mandelate, beginning with “Add 15 mL of dehydrated alcohol.”
Auxiliary Information— Please check for your question in the FAQs before contacting USP.
Topic/Question Contact Expert Committee
Monograph Leonel M. Santos, Ph.D.
Senior Scientific Liaison
(SM12010) Monographs - Small Molecules 1
Reference Standards RS Technical Services
711 Margareth R.C. Marques, Ph.D.
Senior Scientific Liaison
(GCDF2010) General Chapters - Dosage Forms
USP35–NF30 Page 3849