Although I'm not a smoker, I had cigarettes on my mind for most of the day a few weeks ago. While on the road, I had enjoyed Bob Dylan's XM satellite radio program, Theme Time Radio Hour, and the theme was cigarette smoking. Later that same day, I attended our weekly psychiatry lecture, a talk about nicotine dependence by John R. Hughes, M.D., a psychiatrist and noted nicotine researcher at the University of Vermont.

Hughes' lecture focused on important differences between nicotine dependence and dependence on substances like alcohol, heroin, and cocaine. He also discussed various smoking cessation strategies that take into account these differences.

When abused, all of these substances are "behaviorally reinforcing" -- that is, using the substance leads to a high motivation for repeated use, even though the effects are not necessarily pleasurable. These substances also produce physical dependence, may lead to tolerance (i.e., when increasing amounts of a drug are necessary just to produce the same effect), and are associated with withdrawal symptoms when discontinued. Over time, users often end up abusing these substances mainly to avoid the withdrawal effects.

But nicotine dependence from cigarette smoking also has some unique features. First, unlike addictive substances like alcohol, nicotine does not lead to behavioral intoxication — that is, smokers don't get drunk — which may actually encourage more frequent use of and eventual dependence on nicotine. Second, cigarettes are both legal and widely available, two more factors that contribute to their frequent use and abuse.

Other differences:

• Compared with other drug abusers, cigarette smokers generally take many more doses, perhaps a few hundred puffs per day. 
• More of those people who try smoking a cigarette become dependent on nicotine than those who try other commonly abused drugs. (One study showed that 32 percent of those who tried tobacco became dependent, compared with 17 percent trying cocaine, 15 percent trying alcohol, and 9 percent trying marijuana.)

Interestingly, the serious health problems that result from cigarette smoking are from the tar and carbon monoxide, not the addictive substance nicotine. In fact, there may be some benefits from nicotine since, in certain cases, it can improve concentration, decrease anxiety and depression, and lessen hunger.

Anyone who has tried to stop smoking knows how difficult it can be. Although many people can stop smoking through willpower alone, others can get help from smoking cessation treatments. Counseling sessions and self-help groups can be very helpful. Some people quit smoking with the aid of nicotine replacement, which may be supplied by means of a patch, gum, nasal spray, inhaler, or lozenge.

Medications that may aid smoking cessation include Zyban (bupropion) and Chantix (varenicline). The American Cancer Society sponsors a Quitline® tobacco cessation program that links people with trained counselors who can help direct smokers to resources to help them stop. On the Web, the ACS's Guide to Quitting Smoking is one of the most exhaustive sources of information on the subject.

It's a new year. If you haven't already, now's the time to start mustering up the dedication for a successful resolution.