How Addictive is Nicotine?

Answer 1

Generally speaking, nicotine is addictive in two ways. First, nicotine activates the brain's reward system which is a conserved system across species that rewards behaviors that permit survival. Nicotine usurps this system making it highly wanted at the cost of other natural rewards such as food. Strangely, although nicotine activates this system it has a relatively low rewarding value compared to other drugs of abuse like cocaine or heroin. At the pre-clinical setting it is very difficult to get animals to self-administer nicotine which is one reason why it was not considered addictive for many years. To get animals to self-administer nicotine, certain environmental variables need to be in place. This shows that nicotine is interacting somehow with the environment to promote self-administration and subsequent addiction. This leads to the second reason why nicotine is addictive - it interacts with the neural substrates of learning and memory. Acute nicotine enhances learning and memory but not in the good way to make someone super smart. It leads to the formation of strong, maladaptive drug-context associations which triggers cravings and can elicit relapse. Placing a smoker in an environment where they normally smoke (such as a bar in some states) and then expecting them not to crave cigarettes is as absurd as asking someone to forget their name. This dual action of nicotine may be one of the reasons why it is probably the most addictive drug around.

Answer 2

Nicotine is one of the most highly-addictive substances known.