From Smoking to Dependence: The Role of Nicotine Metabolism (Review)

The changing landscape of tobacco products dictates a new paradigm in smoking cessation efforts, which makes the understanding of nicotine metabolic aberrations, its neurobiological effects, and its pathophysiological impact on the human body still relevant. For this purpose, an analysis of publications on the topic was conducted using the medical databases eLIBRARY.RU, PubMed, and Medline (for the period 2000–2024). According to the obtained data, nicotine, a tobacco alkaloid, has a high affinity for brain tissues and produces a range of pharmacological effects, including positive psychoactive effects, leading to the development of strong dependence. Treatment of nicotine dependence involves pharmacotherapy, nicotine replacement therapy, and motivational counseling. Nicotine, although it causes dependence, is not the main cause of smoking-related diseases. The main harm to health is caused by tobacco combustion products. Alternative nicotine delivery systems, such as heated tobacco products and certified electronic cigarettes compliant with Russian national standards, may potentially reduce smoking-related harm, as they do not involve combustion. Electronic cigarettes, or vapes, use liquids, including those containing nicotine, whereas heated tobacco products heat actual tobacco without combustion, which significantly reduces the levels of harmful substances emitted compared to cigarette smoke. These devices are gaining popularity and are the subject of active research. Comprehensive studies of all types of nicotine-containing products available on the Russian Federation market, including heated tobacco products and electronic nicotine delivery systems, are currently of high relevance. These studies should aim to evaluate their impact on consumer health in comparison with traditional cigarette smoking, to assess the potential for integrating their results into clinical guidelines for the prevention and treatment of tobacco-related diseases, and to support the development of up-to-date differentiated regulation in accordance with the actual risk profile of various nicotine-containing products. Considering that modifying smoking-related risk factors remains a highly challenging task, understanding nicotine metabolism, its effects on the human body, and the harm reduction approach implemented through switching from cigarette smoking to alternative nicotine delivery systems may have a positive impact on increasing life expectancy among adult smokers who are not motivated to quit.