The article highlights the necessity of adhering to the literary norms of the Ukrainian language in contemporary medical terminology, particularly the importance of understanding its lexical-grammatical and stylistic levels. The study analyzes term-lexemes that form paronymic relations, as well as the causes and consequences of the unmotivated use of paronyms in scientific discourse (semantic similarity, insufficient understanding of lexical meanings, speakers’ lack of competence). It is found that the erroneous use of paronyms leads to distortion of expressed meaning, linguistic paradoxes, and speech errors. Correct (normative) variants of paronymic medical terms appropriate for the professional language of healthcare practitioners are proposed. The research employs the methods of analysis and synthesis, comparative (contrastive) analysis, and the general linguistic method of scientific description. Conclusions. Quantitative and qualitative changes within the national terminological system result from the interaction of linguistic and extralinguistic factors and regularities. A thorough linguistic analysis of core paronymic pairs (series), their inclusion in lexical minima, and active instructional work with them constitute an important aspect of successfully mastering the language of medicine and improving the quality of specialized medical literature.