You can use it longer without as many side effects. And it gives us an option for people who can't tolerate nicotine replacement products, for whatever reason. Dr. Hurt said researchers thought to look at an antidepressant medicine because other studies have shown that smokers are more likely to have a history of major depression and that nicotine may act as an antidepressant in some smokers. While the precise way the drug works is not completely understood, it affects the same chemical messengers in the brain, called dopamines, as nicotine. Release of dopamine is involved in the pleasure response of drugs of addiction, such as nicotine and cocaine.
Smoking floods the brain with dopamine.