Development and Validation of HPLC Method for Simultaneous Estimation of Ondansetron Dihydrochloride, Famotidine, and Drotaverine Hydrochloride in Rabbit Plasma

Several methods have been reported for the individual determination of Ondansetron (OND), Famotidine (FAM), and Drotaverine (DRO); however, they are not suitable for simultaneously estimating these drugs. Hence, a simple and accurate high-performance liquid chromatographic (HPLC) method was developed and validated for the simultaneous estimation of the three drugs. The method was optimized using the central composite design. The effect of independent variables was optimized while applying the central composite design approach. The quadratic effect of independent variables was significant on the percentage recovery and the retention time ( p  < 0.0001) of the studied drugs. The chromatographic separations were carried out at a 1.5 mL/min flow rate using a 40:60 (v/v) ratio mixture of acetonitrile and phosphate buffer pH 4.8 as optimized parameters. The retention time of OND, FAM, and DRO was observed to be 1.93, 1.45, and 5.46 min, respectively. Similarly, the percentage recoveries of OND, FAM, and DRO were found within the range of 99.16–103.8%, 92.1–101.3%, and 97.6–105.6%, respectively. All the experiments were performed in six replicates (p < 0.05). Hence, the suggested method can be used for the simultaneous determination of OND, FAM, and DRO method can be used for the simultaneous determination of these drugs.