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Cephalexin Tablets for Oral Suspension
» Cephalexin Tablets for Oral Suspension contain not less than 90.0 percent and not more than 110.0 percent of the labeled amount of cephalexin (C12H15N3O2S).
Packaging and storage— Preserve in tight containers at controlled room temperature.
Identification— Mix a quantity of finely powdered Tablets for Oral Suspension with water to obtain a concentration of about 3 mg of cephalexin per mL, and filter (Test solution). Proceed as directed in the Identification test under Cephalexin Capsules, beginning with “Place a suitable thin-layer chromatographic plate”: the RF value of the principal spot obtained from the Test solution corresponds to that obtained from the Standard solution.
Disintegration 701— Tablets for Oral Suspension disintegrate in 3 minutes, using water at 20 ± 5.
Dissolution 711—
Medium: water; 900 mL.
Apparatus 1: Use 40-mesh cloth and 100 rpm.
Time: 30 minutes.
Determine the amount of cephalexin (C12H15N3O2S) dissolved by employing the method specified in the Dissolution test under Cephalexin Tablets.
Tolerances— Not less than 80% (Q) of the labeled amount of cephalexin (C12H15N3O2S) is dissolved in 30 minutes.
Dispersion fineness— Place 2 Tablets for Oral Suspension in 100 mL of water, and stir until completely dispersed. A smooth dispersion is obtained that passes through a No. 25 sieve.
Uniformity of dosage units 905: meet the requirements.
Water, Method I 921: not more than 9.0%.
Residual solvents 467: meet the requirements.
(Official January 1, 2007)
Assay—
Mobile phase, Internal standard solution, Standard preparation, and Chromatographic system— Proceed as directed in the Assay under Cephalexin.
Assay preparation— Prepare a dispersion of not fewer than 20 Tablets for Oral Suspension, accurately counted, using an accurately measured volume of water. Dilute an accurately measured portion of the dispersion quantitatively with water to obtain a solution containing about 1 mg of cephalexin per mL. Pass a portion of the solution through a filter having a 1-µm or finer porosity. Transfer 10.0 mL of the filtrate to a glass-stoppered conical flask, add 15.0 mL of Internal standard solution, and mix.
Procedure— Proceed as directed for Procedure in the Assay under Cephalexin. Calculate the quantity, in mg, of cephalexin (C12H15N3O2S) in each Tablet for Oral Suspension taken by the formula:
(L/D)(CP/1000)(RU / RS),
in which L is the labeled quantity, in mg, of cephalexin in each Tablet for Oral Suspension; D is the concentration, in mg per mL, of cephalexin in the filtrate used to prepare the Assay preparation on the basis of the number of Tablets for Oral Suspension taken, the labeled quantity of cephalexin in each Tablet, and the extent of dilution; and the other terms are as defined therein.
Auxiliary Information— Staff Liaison : Brian D. Gilbert, Ph.D., Scientist
Expert Committee : (MDANT05) Monograph Development-Antibiotics
USP29–NF24 Page 450
Pharmacopeial Forum : Volume No. 28(6) Page 1782
Phone Number : 1-301-816-8223