Development and Validation of HPLC Method for Simultaneous Estimation of Famotidine, Paracetamol and Diclofenac in their Raw Materials and Pharmaceutical Formulation

A simple, sensitive and rapid HPLC method has been developed for simultaneous estimation of a ternary mixture of famotidine, paracetamol and diclofenac in their raw materials and pharmaceutical formulations. The analysis was performed on C₈ column (250 mm × 4.6 mm i.d., 5-μm particle size) with mobile phase consisted of methanol and 0.01 M sodium dihydrogen phosphate (80:20, v/v) with apparent pH 3.5. The UV detector was operated at 280 nm and the effluents were pumped with flow rate of 1.0 mL/min using felodipine as internal standard. The run time under the optimum chromatographic conditions is less than 6 min. Linearity, accuracy and precision were found to be acceptable over the concentration range of 5-100 μg/mL, 10-300 μg/mL and 5-100 μg/mL for famotidine, paracetamol and diclofenac respectively. The sensitivity of the method allows the determination of the studied drugs with limit of quantification of 3.22 μg/mL, 8.93 μg/mL and 4.16 μg/mL for famotidine, paracetamol and diclofenac respectively. The high sensitivity and the simplicity of the proposed method allow the successful determination of the studied drugs in their combined tablets as well as the determination of famotidine in its dosage forms and in its combined tablets with ibuprofen. Moreover, the proposed method was fully validated according to ICH guidelines.