The objective of the study was to develop a simple, accurate, precise and rapid UV second order derivative spectrophotometric method with subsequent validation by using ICH guidelines for the determination of ofloxacin and ornidazole by using 0.1N hydrochloric acid as the solvent in combined dosage form. The proposed second order derivative method involves the measurement of absorbance of one drug at zero crossing point of other; hence 234.6 nm and 212.8 were selected for the estimation of ofloxacin and ornidazole respectively. The linearity of the proposed method was found in the concentration range of 2 – 10 μg /ml (r2= 0.9953) for ofloxacin and 2.0 – 10 μg /ml (r2= 0.9954) for ornidazole respectively. The percentage mean recovery was found to be 99.792 % for ofloxacin and 99.988 % for ornidazole respectively. The method was also statistically validated for its linearity, accuracy and precision. Both intra and inter day variation showed less percentage (%) RSD values indicating high grade of precision of this method.
