METHOD DEVELOPMENT AND VALIDATION FOR THE SIMULTANEOUS ESTIMATION OF BILASTINE AND MONTELUKAST IN BULK AND PHARMACEUTICAL DOSAGE FORMS BY RP-HPLC

A robust, accurate, and precise reverse-phase high-performance liquid chromatography (RP-HPLC) method was developed and validated for the simultaneous estimation of Bilastine and Montelukast in bulk and pharmaceutical dosage forms. The chromatographic separation was achieved using a C18 column (150 x 4.6 mm, 5 µm) with an optimized mobile phase and a flow rate of 1.0 mL/min. Detection was performed at 260 nm. The method was validated according to ICH guidelines, demonstrating excellent linearity (R² > 0.999), accuracy (98–102% recovery), and precision (%RSD < 2.0%). The developed method was also found to be robust and specific, ensuring no interference from excipients. The results confirm the method’s suitability for routine quality control analysis of Bilastine and Montelukast in pharmaceutical formulations.