Oxtriphylline Extended-Release Tablets
» Oxtriphylline Extended-Release Tablets contain an amount of oxtriphylline equivalent to not less than 90.0 percent and not more than 110.0 percent of the labeled amount of anhydrous theophylline (C7H8N4O2).
Packaging and storage— Preserve in tight containers.
Labeling— Label the Tablets to state both the content of oxtriphylline and the content of anhydrous theophylline. The labeling indicates the Dissolution Test with which the product complies.
USP Reference standards 11
USP Oxtriphylline RS Click to View Structure
Identification—
A: The retention time exhibited by theophylline in the chromatogram of the Assay preparation corresponds to that of theophylline in the chromatogram of the Standard preparation, as obtained in the Assay.
B: Transfer a quantity of finely ground Tablets, equivalent to about 100 mg of oxtriphylline, to a suitable test tube, and proceed as directed in Identification test B under Oxtriphylline Delayed-Release Tablets, beginning with “add 10 mL of methanol.”
Dissolution 711
test 1 (for products labeled as 400-mg tablets)—If the product complies with this test, the labeling indicates that it meets USP Dissolution Test 1. Proceed as directed for Method B under Apparatus 1 and Apparatus 2, Delayed-Release Dosage Forms, except to use Acceptance Table 2.
pH 7.5 Buffer— Transfer 27.22 g of monobasic potassium phosphate to a 4-L volumetric flask, add 1 L of water and 816 mL of 0.2 N sodium hydroxide, and dilute with water to about 3800 mL. Adjust with 0.2 N sodium hydroxide or phosphoric acid to a pH of 7.5, and dilute with water to volume.
Medium: 0.1 N hydrochloric acid for the first hour, then pH 7.5 Buffer; 900 mL.
Apparatus 2: 50 rpm.
Procedure— Determine the amount of C12H21N5O3 dissolved from UV absorbances at the wavelength of maximum absorbance at about 248 nm on filtered portions of the solution under test, diluted with Medium if necessary, in comparison with a Standard solution having a known concentration of USP Oxtriphylline RS in the same Medium.
Times and Tolerances—
Time (hours) Amount dissolved
1 between 5% and 30%
3 between 50% and 70%
5 between 65% and 85%
7 not less than 75%
test 2 (for products labeled as 600-mg tablets)—If the product complies with this test, the labeling indicates that it meets USP Dissolution Test 2. Proceed as directed for Method B under Apparatus 1 and Apparatus 2, Delayed-Release Dosage Forms, except to use Acceptance Table 2.
pH 7.5 Buffer, Apparatus, Medium, and Procedure Proceed as directed for Test 1.
Times and Tolerances—
Time (hours) Amount dissolved
1 between 15% and 40%
3 between 50% and 70%
7 not less than 75%
Uniformity of dosage units 905: meet the requirements.
Assay— Proceed as directed in the Assay under Oxtriphylline Delayed-Release Tablets, using Oxtriphylline Extended-Release Tablets.
Auxiliary Information— Please check for your question in the FAQs before contacting USP.
Topic/Question Contact Expert Committee
Monograph Mary S. Waddell
Scientific Liaison
1-301-816-8124
(SM42010) Monographs - Small Molecules 4
Reference Standards RS Technical Services
1-301-816-8129
rstech@usp.org
711 Margareth R.C. Marques, Ph.D.
Senior Scientific Liaison
1-301-816-8106
(GCDF2010) General Chapters - Dosage Forms
USP35–NF30 Page 4163
Pharmacopeial Forum: Volume No. 31(1) Page 174