A Validated Stability Indicating LC Method for Simultaneous Estimation of Phenylephrine and Ebastine in Combined Pharmaceutical Dosage Form and their Application to Stress Degradation Studies

A simple, sensitive and reproducible stability indicating RP-HPLC method for the simultaneous determination of Phenylephrine and Ebastinein bulk and Pharmaceutical dosage formhas been developed and validated. Chromatographic separation was carried out on kromasil C18 (250×4.6mm, 5mparticle size) column using a mobile phase composed of Phosphate buffer (adjusted to pH 5.0 with dilute OPA): acetonitrile: methanol in the ratio of 30:45:25 %v/v/vat a flow rate of 0.8 ml/min. The analyte was monitored using PDA detector wavelength at 211 nm. The retention time was found to be 2.295 min and 4.225 min for Phenylephrine and Ebastine respectively. The proposed method was found to be having linearity in the concentration range of 25-150µg/ml for both Phenylephrine(r20.99996)and Ebastine(r20.99987)respectively. The developed method has been statistically validated according to ICH guidelines. Stress testing which covered acid, alkali, peroxide, photolytic and thermal degradation was performed on under test to prove the specificity of the method and the degradation was achieved. The proposed method can be successfully applied for the stability indicating RP-HPLC simultaneous determination of Phenylephrine and Ebastine in bulk and combined tablet dosage form and in routine quality control analysis.