Medium: 1%sodium lauryl sulfate;900mL.

Apparatus 2: 75rpm.

Time: 60minutes.

Procedure— Determine the amount of C24H32O4dissolved from UVabsorbances at the wavelength of maximum absorbance at about 292nm of filtered portions of the solution under test,suitably diluted with 1%sodium lauryl sulfate,if necessary,in comparison with a Standard solution having a known concentration of USP Megestrol Acetate RSin the same Medium.

Tolerances— Not less than 75%(Q)of the labeled amount of C24H32O4is dissolved in 60minutes.

Procedure for content uniformity— Place 1Tablet in a volumetric flask of suitable size so that the final expected solution concentration is between about 0.2and 1.0mg of megestrol acetate per mL.Add 1mLof water,and gently shake until the Tablet has disintegrated.Fill the flask to three-quarters of its nominal capacity with methanol,and shake by mechanical means for 20minutes.Dilute with methanol to volume,mix,and filter,discarding the first 15mLof the filtrate.Dilute 5.0mLof the subsequent filtrate quantitatively with methanol to obtain a solution containing about 10µg of megestrol acetate per mL.Prepare a Standard solution of USP Megestrol Acetate RSin the same medium having a known concentration of about 10µg per mL.Record the absorbances of the solutions in 1-cm cells,against a blank of methanol,scanning from 350nm to 260nm.Measure the absorbances at the wavelength of maximum absorbance at about 288nm.Calculate the quantity,in mg,of C24H32O4in the Tablet taken by the formula: in which Tis the labeled quantity,in mg,of megestrol acetate in the Tablet;Cis the concentration,in µg per mLof USP Megestrol Acetate RSin the Standard solution;Dis the concentration,in µg per mL,of the solution from the Tablet,based upon the labeled quantity per Tablet and the extent of dilution;and AUand ASare the absorbances of the solution from the Tablet and the Standard solution,respectively.

Mobile phase,Solvent mixture,Internal standard solution,Standard preparation,andChromatographic system— Prepare as directed in the Assayunder Megestrol Acetate.

Assay preparation— Weigh and finely powder not fewer than 20Tablets.Transfer an accurately weighed portion of the powder,equivalent to about 80mg of megestrol acetate,to a 100-mLvolumetric flask.Add about 10mLof water,and shake for 10minutes.Add 75mLof acetonitrile,and shake for 30minutes,then dilute with acetonitrile to volume,and mix.Place a 25-mLaliquot in a glass-stoppered,35-mLcentrifuge tube,insert the stopper,and centrifuge for 10minutes.Transfer 5.0mLof the supernatant and 5.0mLof Internal standard solutionto a 50-mLvolumetric flask,dilute with Solvent mixtureto volume,and mix.

Procedure— Proceed as directed for Procedurein the Assayunder Megestrol Acetate.Calculate the quantity,in mg,of megestrol acetate (C24H32O4)in the portion of Tablets taken by the formula: in which the terms are as defined therein.