Advanced measurement techniques, allowing the confirmation of the identity of the active substance and excipients contained in the finished product are the basic methods of the analysis of the drug. Terahertz radiation (in the range of 2 cm-1 and 130 cm-1) can be used to identify substances in the process of their production, which is directly related to quality control and production safety. Terahertz spectroscopy technique allows conducting qualitative and quantitative analysis of active ingredient and excipients in the drug form, in particular, is used to identify the polymorphic forms and pseudopolymorphic substances and obtain information about homogeneity tablet film coats. It is a modern, noninvasive and nondestructive method of analysis of pharmaceutical products allowing for simultaneous image acquisition of the sample and recording the spectra of different components included in the sample.

Keywords: terahertz spectroscopy, pharmaceutical analysis, polymorphism, hydrates, phase transition monitoring, PAT.