Everyone realizes the benefits that ensue when a longtime smoker is able to stop. Epidemiologic studies suggest that about one-third of smokers are nicotine-dependent (i.e., they have the brain reward system dysregulation associated with not being able to quit). But it appears that the number of people who have difficulty quitting is much higher. Not only is nicotine dependence producing, but the smoking “habit” (smoking while drinking, or after a meal, or wanting to have something to do with one's hands) often can be very difficult to break, as well. Some people don't even want to quit, because they either deny that any serious consequences could occur for them, are afraid of withdrawal, or don't want to gain weight.
Carlton K. Erickson, PhD
Many treatment centers are becoming smoke-free, and effective evidence-based methods now exist for getting people off both their drug of choice and tobacco during the same treatment period. I remember the days when treatment centers refused to push smoking cessation programs for alcoholics for fear of losing patients. The idea of an alcoholic becoming abstinent on two drugs at one time was amazingly not popular, and some of that old stigma still exists. But now we often see patients requesting nicotine patches when they enter treatment for alcohol and other drug dependence.
Several antismoking aids are now on the market or on the horizon. In addition to nicotine replacement therapy (NRT), the medications bupropion (Zyban) and the newly approved varenicline (Chantix) are now available. Also, a drug that has shown promise in Europe will likely be approved in the near future. Rimonabant (Acomplia, with a possible U.S. trade name Zimulti) and varenicline now merit the field's attention.
Varenicline studies promising
Varenicline is pharmacologically known as an alpha4beta2 nicotinic acetylcholine receptor partial agonist, which means that it activates the brain's nicotinic receptors in a manner similar to nicotine, but with less affinity (effect). Its therapeutic usefulness comes from the idea that by activating the same receptor as nicotine, varenicline will reduce nicotine craving and withdrawal. Indeed, one of three randomized studies on varenicline published in the July 2006 issue of the Journal of the American Medical Association reported that varenicline is more effective than bupropion or placebo for smoking cessation.1
Side effects of this drug are described as being minimal, with nausea cited most frequently. Long-term outcome studies indicate smoking cessation in about 50% of patients given the drug; outcome studies so far have not gone beyond one year. Questions remain about drug interactions, long-term side effects, and possible dependence production.
Rimonabant and weight
Rimonabant is the only medication of the new endocannabinoid class of drugs that is in clinical study in the United States. This drug, a cannabinoid receptor antagonist (receptor blocker), has been used in the United Kingdom for treating obesity and smoking. The FDA recently granted a letter of approval for rimonabant for the treatment of obesity, but did not approve it for smoking cessation. It is believed that rimonabant may be approved for smoking cessation in 2007.
Rimonabant could prove to be an extremely beneficial medication, since so many people gain weight when they stop smoking. Rimonabant actually could help people maintain body weight when they stop smoking.
Smoking is such a dangerous pastime that more tools for recovery from nicotine dependence are urgently needed. Anyone concerned about side effects of the aforementioned medications should remember to conduct a risk/benefit analysis. In essence, the great benefit of smoking cessation greatly outweighs the possible side effects of antismoking medications. The other treatment rule is that such medications always should be accompanied by supportive counseling to help the client in the quest for a healthier lifestyle.
Carlton K. Erickson, PhD, is Director of the Addiction Science Research and Education Center at the University of Texas at Austin's College of Pharmacy.
- Jorenby DE, Hays JT, Rigotti NA, et al. Efficacy of varenicline, an alpha4beta2 nicotinic acetylcholine receptor partial agonist, vs. placebo or sustained-release bupropion for smoking cessation: A randomized controlled trial. JAMA 2006; 296:56-63.