Packaging and storage— Preserve in well-closed,light-resistant containers.

USP Reference standards á11ñ— USP Brompheniramine Maleate RS.

Identification— Transfer a volume of Oral Solution,equivalent to about 50mg of brompheniramine maleate,to a separator,render distinctly alkaline with 1Nsodium hydroxide,and extract with two 50-mLportions of chloroform,shaking gently to avoid emulsification.Wash the combined chloroform extracts with 10mLof water,and discard the aqueous phase.Filter the combined chloroform extracts into a conical flask,and evaporate the solvent on a steam bath,with the aid of a current of air.To the residue add 25mLof dilute hydrochloric acid (1in 1200),and proceed as directed under Identification—Organic Nitrogenous Bases á181ñ,beginning with “Transfer the liquid to a separator.”The Oral Solution meets the requirements of the test.

pHá791ñ: between 2.5and 3.5.

Alcohol content,Method Iá611ñ: between 2.7%and 3.3%of C2H5OH.

Assay— Transfer an accurately measured volume of Oral Solution,equivalent to about 20mg of brompheniramine maleate,to a separator,render distinctly alkaline with 1Nsodium hydroxide,and extract with ten 10-mLportions of chloroform,shaking gently to avoid emulsification.Wash the combined chloroform extracts with 10mLof water,wash the latter with 20mLof chloroform,and discard the aqueous phase.Quantitatively filter the combined chloroform extracts and washings into a conical flask,and evaporate the solvent on a steam bath,with the aid of a current of air.To the residue add 25mLof glacial acetic acid and 5mLof acetic anhydride,agitate,and allow to stand for about 15minutes.Add 1drop of crystal violet TS,and titrate with 0.01Nperchloric acid VSto a blue-green endpoint.Perform a blank determination,and make any necessary correction.Each mLof 0.01Nperchloric acid is equivalent to 2.177mg of brompheniramine maleate (C16H19BrN2·C4H4O4).

(Official June 1,2005)

Expert Committee:(PA1)Pharmaceutical Analysis 1

USP28–NF23Page 288

Phone Number:1-301-816-8379