Abstract: Indomethacin hydrazide is a very important compound in the medical field prepared recently to reduce the side effects of indomethacin. The role of the drug is as a non-steroidal anti-inflammatory. Therefore, the methods for estimating this important compound are very few. In this study, an easy, inexpensive and fast spectrophotometric method has been proposed for the determination of this compound in various samples. The method is based on two steps, the first step is the oxidising of indomethacin hydrazide with the oxidizing agent N-bromosuxinamide in an acidic medium, where a compound is formed, and gradually shortens the reddish-orange colour of the xylenol orange dye with the steady increase of indomethacin hydrazide in the second step. The orange xylenol dye is of great importance as it is used in removing a lot of pollution damage, especially contamination with metals, where these minerals are complexes with the xylenol dye and are separated and removed. Besides the important use of this dye in the removal of oxidation products of drugs, as in the case of the indomethacin derivative, after it had been converted to the oxidised formula with the aid of oxidising agents. This method obeyed Beer’s law at the concentration range from 2-28 μg/mL, Sandall’s value was 0.1547 μg-2 cm-1, while the molar absorptivity value was 5.77×104 L mol-1 cm-1. The method was successfully applied to determine the amount of indomethacin hydrazide in different samples.
