The essential feature of Substance Dependence is a cluster of cognitive, behavioral, and physiologic symptoms indicating that the individual continues use of the substance despite significant substance-related problem.Cigarette smoke consists of volatile chemical substances (92%) and particulate material (8%) resultant of tobacco combustion. Nicotine, a tertiary volatile amine, is the most important active tobacco component Nicotine is rapidly absorbed by the lung alveolus and reaches the brain within 10 seconds. Its half-life is of approximately 2 hours, and metabolization is mostly hepatic, through P450 cytochrome. The main enzyme involved is CYP2A6. Molecular biology studies demonstrate that capacity in metabolizing nicotine varies according to each individual7.
The tobacco dependence treatment systems at different stages of development of their systems, and from different income levels and regions of the world, and to draw some lessons from their experiences that might be useful to other countries. Nicotine replacement therapy presents good outcomes when associated with bupropion, although it also has limitations, besides not being considered for patients with severe cardiovascular diseases.Of the 71 patients, 47 (66.2%) presented with high or very high ND, 40 (56.3%) smoked more than 20 cigarettes/day, and 32 (45.1%) smoked their first cigarette within 5 min of awakening. Advanced disease stage correlated significantly with the number of cigarettes smoked per day (p = 0.011) and with smoking history (p = 0.047).In most of the patients studied, the level of ND was high or very high. The prevalence of heavy smoking for long periods was high in our sample.