ABSTRACT:
This work presents a simple, reproducible, sensitive, generic and efficient method for simultaneous estimation. Vierordt’s method or simultaneous equation method was developed and validated for simultaneous estimation of two mixtures: Tadalafil and Dapoxetine, Vardenafil and Dapoxetine, in the pure and pharmaceutical dosage form. The method was based on the measurement of absorbance at two wavelengths for each mixture in methanol. Calibration curves of all drugs were found. with a good correlation coefficient values of more than 0.99. The RSD values were found within limits and the recoveries ranging from 98 to 102% which confirms that the proposed method is accurate. This method for simultaneous estimation is simple, economical and can be applied successfully for the simultaneous estimation of dapoxetine and his combinations with Tadalafil and Vardenafil in the pure and pharmaceuticals dosage forms.