College of Education, University of Samarra discussed a master dissertation on the quantification of some decongestant drugs using their relative derivative by the postgraduate student, Mrs. Wasan Jafar Sadiq.   The dissertation aimed at using simple, accurate, sensitive, rapid and economical spectrophotometric methods for the determination of the drugs trifluoperazine hydrochloride, isopropamide iodide and xylometazoline hydrochloride in their pure form and in their pharmaceutical preparations.   The dissertation demonstrated thre Vis-Uv absorption spectroscopy, the method of spectrometry, Beer-Lambert law and an overview of the drug compounds under study, its chemical composition, characteristics and uses and the most important analytical methods used in its estimation.   The dissertation highlighted that the used method is derived from the ratios of the spectra that divide the absorption spectrum of the mixture of the two drugs by the absorption spectrum of one of the two drugs, which is considered overlapping that the product of the division process is the absorption spectrum of the other drug to be estimated and the spectrum of a drug mixture of TFBH with a concentration of (2-40) mcg was divided. .ml-1 with IPI on the IPI absorption spectrum at a concentration of 10 mcg.ml-1 to obtain the relative spectrum of each of the mentioned concentrations for determination of TFBH.