A: The retention time of the major peak in the chromatogram of the Assay preparationcorresponds to that of the Standard preparationas obtained in the Assay.

B: Transfer a quantity of finely ground Tablets,equivalent to about 50mg of metoclopramide,to a suitable flask,add 5mLof water,shake by mechanical means,and filter.Add to the filtrate 5mLof a 1in 100solution of p-dimethylaminobenzaldehyde in 1Nhydrochloric acid:a yellow-orange color is produced.

Medium: water;900mL.

Apparatus 1: 50rpm.

Time: 30minutes.

Procedure— Determine the amount of C14H22ClN3O2dissolved from UVabsorbances at the wavelength of maximum absorbance at about 309nm of filtered portions of the solution under test,suitably diluted with water,if necessary,in comparison with a Standard solution having a known concentration of USP Metoclopramide Hydrochloride RSin the same medium.

Tolerances— Not less than 75%(Q)of the labeled amount of C14H22ClN3O2is dissolved in 30minutes.

Mobile phase,Standard preparation,System suitability solution,andChromatographic system— Prepare as directed in the Assayunder Metoclopramide Injection.

Assay preparation— Weigh and finely powder not less than 20Tablets.Transfer an accurately weighed portion of the powder,equivalent to about 40mg of metoclopramide,to a 100-mLvolumetric flask,add about 70mLof 0.01Mphosphoric acid,and sonicate for 5minutes.Cool to room temperature,dilute with 0.01Mphosphoric acid to volume,and mix.Filter the solution through a 0.45-µm filter,discarding the first portion of the filtrate.Transfer 10.0mLof this solution to a 100-mLvolumetric flask,dilute with 0.01Mphosphoric acid to volume,and mix.

Procedure— Proceed as directed for Procedurein the Assayunder Metoclopramide Injection.Calculate the quantity,in mg,of metoclopramide (C14H22ClN3O2)in the portion of Tablets taken by the formula: in which 299.80and 336.26are the molecular weights of metoclopramide and anhydrous metoclopramide hydrochloride,respectively;Cis the concentration,in µg per mL,of USP Metoclopramide Hydrochloride RS,on the anhydrous basis,in the Standard preparation;and rUand rSare the peak responses of metoclopramide obtained from the Assay preparationand the Standard preparation,respectively.