DefinitionBy Mayo Clinic staff Nicotine dependence is an
addiction to tobacco products caused by the drug nicotine.
Nicotine dependence — also referred to as tobacco dependence —
means you can't stop using the substance, even though it's
causing you harm. While it's the nicotine in tobacco that causes
nicotine dependence, the toxic effects come mainly from other
substances in tobacco. Smokers have much higher rates of heart
disease, stroke and cancer than do nonsmokers. Nicotine produces
physical and mood-altering effects in your brain that are
temporarily pleasing. These effects make you want to use tobacco
and lead to dependence. At the same time, stopping tobacco use
causes withdrawal symptoms, including irritability and anxiety.
Many effective treatments for nicotine dependence are available
to help you manage withdrawal and stop smoking for good. Ask
your doctor for help. - Nicotine. NIDA for Teens.
http://www.teens.drugabuse.gov/drnida/drnida_nic1.asp. Accessed
Sept. 15, 2010. - Questions about smoking,