Background: The use of nicotine-containing tobacco is among the substances with the highest dependence potential. The negative impact and consequences of cigarette use are discussed not only among experts. In contrast, nicotine replacement therapy and user experience are unspecified. Aims: The primary goal of the research was to map the experience of clients of the National Tobacco Quitline Czech Republic with the use of nicotine replacement therapy in the treatment of tobacco addiction. The categories examined include: dosage of replacement nicotine, preferred forms of replacement nicotine, reported adverse effects, and route of administration of replacement nicotine. The study was carried out in order to refine the dosage of nicotine replacement therapy, increase the compliance of nicotine replacement users and increase the quality of services provided by the National Tobacco Quitline Czech Republic. Methods: The study was carried out with the help of a qualitative research methodology. Respondents were selected using the method of intentional selection according to defined properties. Data was created using a structured interview with open-ended questions and semi-structured interviews. The research data were processed using the open coding method and the method of capturing formulas was used...