Spectrophotometric determination of Fexofenadine hydrochloride

A simple and sensitive spectrophotometric method has been developed for the determination of fexofenadine hydrochloride in bulk and pharmaceutical dosage forms. The method is based on the chloroform-extractable pale yellow colour complex formed by the reaction of fexofenadine with bromothymol blue at pH 2.6. The chromogen can be estimated at 412 nm against a reagent blank. This method obeys Beer's law in the concentration range of 10-50 µg/ml of the drug. The optimum reaction conditions and other analytical parameters were also evaluated. The proposed method has been successfully applied to the analysis of bulk drugs and their dosage forms.