A simple and sensitive extractive spectrophotometric method has been described for the assay of cetirizine dihydrochloride in
pure and different pharmaceutical preparations. The method was based on the formation of the ion-pair complex from the reaction
between cetirizine dihydrochloride and methyl orange in pH 4.0, which gave a yellow color after chloroform extraction and exhibited
a maximum absorbance at 424.5 nm. Beer's law was obeyed in the concentration range of 2.5 - 20 μg/mL. The method was
tested and validated for various parameters according to ICH guidelines.