Nicotine Addiction: Role of the Nicotinic Acetylcholine Receptors Genetic Variability in Knowledge, Prevention and Treatment

In 1988 the US Surgeon General’s report stated that tobacco use, in any form, is addicting as a result of its nicotine content and defined the processes determining tobacco addiction as “similar to those that determine addiction to drugs such as heroin and cocaine” (U.S. Surgeon General, 1988). Tobacco smoking has been classified by the WHO International Classification of Diseases (ICD-10) under the "Mental and behavioural disorders” (F00-F99 (http://apps.who.int/classifications/apps/icd/icd10online/). Continuous use of nicotine induces adaptive changes in the CNS leading to tolerance, physical or physiological dependence, sensitization, craving, reward and relapse. Drug addiction has been defined by Koob (2008) as "a chronically relapsing disorder characterized by compulsive drug use and loss of control over drug intake". Indeed Koob (2008) proposed that addiction includes three different stages, which are: "preoccupation/anticipation, binge/intoxication, and withdrawal/negative affect". As a final result chronic use of nicotine produces ‘tolerance’, an occurrence that reduces the effect of a drug given dose (Fig. 1.).