[Nicotine dependence--medico-biological aspects].

The nicotine in tobacco products is strongly addictive. This was generally recognised no earlier than in the late 1970s, though it was well known within the international tobacco industry in the early 1960s. Nicotine acts as an addictive substance by binding to acetylcholine receptors and causing the release of dopamine in the brain, though other signalling substances are also important for the action of nicotine in the central nervous system. Withdrawal syndrome is the typical evidence of physical addiction to nicotine. Nicotine addiction can develop rapidly. There are, however, individual differences; genetic predisposition may have a bearing on these differences.