The article proposes methods for determination of clopidogrel and metamizole sodium in flush water off industrial equipment using multi-wavelength UV spectrometry and calculation of areas under curves. The research concerns with recording the spectra in aqueous solution without preliminary pH adjustment. We performed numerical integration of spectra in the wavelength range from 210 to 290 nm for clopidogrel, and from 220 to 320 nm for sodium metamizole. The methods allow ones to determine clopidogrel and sodium metamizole in solution in the concentration range of 1-100 mg/l. Indeed, the methods do not require extensive sample preparation and complicated analytical equipment. These methods are suitable for routine determination of these compounds in flush water off industrial equipment.