TOBACCO: DEPENDENCE

In the United States as of 1999, there were about 57 million cigarette smokers-representing 25 percent of the adult population. Another 5 percent (men) use smokeless tobacco (chewing tobacco or snuff). Most (70-80%) say they would like to quit. Unfortunately, they are dependent on (addicted to) nicotine, an alkaloid that makes it difficult to stop using tobacco. Most of them will have to try to quit several times before they are successful. Both the direct effects of nicotine on the body and behavioral associations with those effects learned over the years of tobacco use keep people going back for more even when they want to quit.

The role of nicotine in tobacco use is complex. Nicotine acts on the body directly to produce effects such as pleasure, arousal, enhanced vigilance, relief of anxiety, reduced hunger, and body-weight reduction. It may also reverse the withdrawal who is symptoms that occur in a nicotine-dependent person trying to quit, when nicotine levels in the body fall. These symptoms include anxiety, irritability, difficulty concentrating, restlessness, hunger, depression, sleep disturbance, and craving for tobacco. When this happens, the use of nicotine (whether tobacco or nicotine-containing medications) usually makes people feel better by reversing the unpleasant withdrawal symptoms.

Nicotine also acts indirectly, through a learning process that occurs when the direct effects of nicotine occur repeatedly in the presence of certain features of the environment. As a result of the learning process, called conditioning, formerly insignificant environmental factors become cues for the direct actions of nicotine. These factors can become either pleasurable in themselves or they can serve as a triggering mechanism for lighting up a cigarette. For example, the taste, smell, and feel of tobacco often evoke a neutral response and sometimes repugnance in a nonsmoker. After years of experiencing the direct effects of nicotine in the presence of tobacco, however, a smoker finds the sensory aspects of tobacco pleasurable.

The indirect or conditioned effects of nicotine are responsible for much more complicated learning than the learning associated with nicotine's direct effects. Conditioning is also the process whereby the situations in which people often smoke such as after a meal, with a cup of coffee, with an alcoholic beverage, while doing a task at work, while talking on the phone, or with friends who also smoke become in themselves powerful cues for the urge to smoke. When people stop using tobacco, therefore, the direct effects of nicotine are not the only pleasures they must give up. They must also learn to forgo the indirect effects of nicotine: those experiences that, through learning, have become either pleasurable in themselves or a cue to smoke.

MOTIVATION FOR QUITTING

Most Americans who use tobacco would like to quit, and the reasons for wanting to quit vary. The most common include (1) a concern for one's health; (2) a concern for the health of one's family and friends (this may entail concern about the harmful effects on children of secondhand smoke or concern about setting a bad example for them); (3) social pressure; (4) and economic factors (cigarettes are expensive).

STAGES OF QUITTING

Successful quitting of tobacco use usually occurs as a process over time, a series of mental stages or steps that the smoker goes through in quitting: 1. Precontemplation. The person is smoking and is not motivated to stop smoking during this stage. 2. Contemplation. The person is still using tobacco and is motivated to quit but has not settled on a quit date that is within one month. 3. Action. The person has a stop date and a plan that was either already implemented or will be implemented within one month. 4. Maintenance. The person has discontinued the regular, daily use of tobacco for a minimum of one month.

RELAPSE

Most tobacco users who try to quit agree with Mark Twain, who said, "To cease smoking is the easiest thing I ever did; I ought to know because I've done it is a thousand times." People who are addicted to tobacco and who try to quit are able to do so for a brief period of time, but most resume smoking. For example, 66 percent of smokers who try to quit on their own or with minimal outside help relapse within 2 days, 90 percent relapse within 3 months, and 95 percent to 97 percent relapse within 1 year of quitting. The key to successful smoking cessation is an understanding of what triggers relapse, and what strategies are effective in preventing relapse. Some of the most important triggers for lighting up a cigarette are withdrawal symptoms, environmental cues acquired through learned associations, and emotional upset. Relapse is promoted by such common withdrawal symptoms as difficulty concentrating, irritability, and weight gain. Environmental cues to relapse include the presence of other smokers such as a spouse, friends, or coworkers who smoke and occasions when alcoholic beverages are consumed. Emotional upset and depression are also commonly reported cues for lighting up.

MANAGING URGES TO SMOKE

A smoker who contemplates quitting often thinks that smoking cessation is a simple matter of refraining from smoking during a period of nicotine withdrawal. Urges to smoke are powerful, however, and occur long after the period of nicotine withdrawal has ended. Tobacco users must not only not smoke but must, in fact, learn a new, tobacco-free lifestyle. Some learn on their own; others seek professional help. Key aspects of learning a tobacco-free lifestyle include anticipating and managing withdrawal symptoms and environmental triggers for smoking. The environment might be managed to minimize smoking triggers by, for example, (1) sitting in nonsmoking sections of restaurants; (2) removing ashtrays from one's home and office; (3) leaving the table as soon as possible after meals and engaging in other activities such as talking, walking, or doing the dishes; (4) avoiding (at least temporarily) situations that trigger smoking, such as drinking alcohol or coffee when smokers are around and going to places, parties, or bars where people smoke; (5) actively seeking social support for smoking cessation. The encouragement of a husband or wife, or of friends and others who have quit or are in the process of quitting, also makes it easier. Smokers who enjoy handling cigarettes or having something in their mouths need to substitute something for these smoking-related behaviors. They may chew gum, toothpicks, sunflower seeds, or something similar; munch food or low-calorie snacks; exercise to take up time they might otherwise spend smoking and to reduce any weight gain; snap, roll, or twist rubber bands on their wrist. What people think about while quitting is an important factor in relapse. They need to teach themselves to maintain thoughts that may be useful in overcoming urges to smoke. Instead of thinking about the expected pleasures of a cigarette, the would-be quitter can substitute a stream of thoughts about the risks of smoking, the benefits of not smoking, the commitment to not smoking, the pleasures of an anticipated reward for not smoking, or the day's next activity. Stress management is also important for successful quitting. Smokers soon recognize that giving up smoking is a substantial stress in itself. They can resort to some strategies that may reduce stress, such as meditation, relaxation, and physical exercises. Other aspects of self-management during smoking cessation include setting realistic goals and some sensible rewards for behavior that leads to reducing tobacco use. Some days a realistic goal is a short-term one and involves just getting through each urge to smoke without succumbing. The smoker who is quitting can use any of the already mentioned substitution or distraction strategies while remembering that urges to smoke are likely to continue to come and go for some time. Rewarding oneself for meeting even the short-term goals is important. Rewards for not using tobacco can include new clothes, a new book, time to develop a new hobby, or anything else the former smoker might enjoy. Many rewards can be paid for from money saved by not buying tobacco.

INDEPENDENT QUITTING

Most smokers quit smoking without professional help. People who quit on their own can benefit by (1) clearly identifying the reasons they want to quit (i.e., health, cost of cigarettes, etc.); (2) anticipating potential barriers to or problems with quitting and how to manage them; (3) setting a firm quit date and on that date removing all cigarettes and ashtrays from the home or office. In addition, any friends or family members who smoke should be asked not to offer cigarettes. Persistence in trying to quit almost always works. Smoking a cigarette in the course of trying to quit should not become the end of the smoking-cessation effort. Most smokers try to quit several times before they are successful. Many aids are available to tobacco users who quit on their own. Smoking-cessation program guides and motivational and educational tapes—audiotapes and videotapes—may be obtained from physicians, hospitals, or organizations such as the American Lung Association, the American Cancer Society, or the American Heart Association, or they may be found in bookstores and libraries.

ASSISTED QUITTING

Smoking-Cessation Programs.

These programs are available to help smokers in most communities. They usually involve attending meetings made up of small groups of quitting smokers who discuss their reasons for not smoking, their problems with quitting, and how they manage these problems. Participants in the programs can pick up practical skills in managing their smoking-cessation attempts and also obtain social support for their efforts. The cessation programs are offered by public-health organizations such as the American Lung Association and the American Cancer Society, and also by private companies such as Smokestoppers and Smokenders.

Physician- and Clinic-Assisted Quitting.

Many physicians' offices and some hospital clinics offer assistance in smoking cessation. The clinics are particularly useful for people who have medical problems that need to be treated at the same time, for people who have tried before and failed to quit, or for people who may benefit from taking nicotine-replacement medications. Smokers can turn to these health-care facilities for advice on how to quit and for self-help material as well as for support and information during the different stages of quitting.

Pharmacotherapies for Tobacco Dependence.

Medications for tobacco dependence are categorized as first-line or second-line depending on the level of evidence supporting their efficacy. First-line medications include the nicotine replacement systems, i.e., nicotine chewing gum, nicotine patch, nicotine nasal spray, and nicotine inhaler, and bupropion. Second-line medications include nortriptyline and clonidine, and combination nicotine replacement therapy.

Nicotine replacement treatments.

Recent research has shown that nicotine replacement increases by about twofold the likelihood of a person successfully quitting smoking. Nicotine-replacement therapy can reduce the severity of nicotine withdrawal. Some tobacco users are concerned about the hazards of taking in nicotine, but the hazards of nicotine-replacement therapy are much less than those associated with smoking. In the first place, the amount of nicotine ingested in replacement therapies is less than that taken in from cigarettes. In the second place, nicotine-replacement medications do not expose smokers to the other hazards of cigarette smoke which include carbon monoxide, tar, cyanide, and a number of other toxic substances. On balance, using the nicotine replacement systems is much safer than smoking cigarettes.

The nicotine-replacement medications are particularly useful with more seriously addicted smokers, but they are not a simple cure; rather, they must be used as part of a program of learning to live a tobacco-free lifestyle. Currently, four nicotine-replacement products are marketed in the United States: nicotine chewing gum (also called Nicorette), nicotine patches (also called transdermal Nicotine Delivery Systems), nicotine nasal spray, and nicotine inhaler.

Nicotine Chewing Gum.

Nicotine chewing gum contains nicotine (bound to a resin, a chemical substance that binds other chemicals) and sodium bicarbonate. The sodium bicarbonate is necessary for keeping the saliva at an alkaline (basic) pH, which in turn is necessary for allowing nicotine to cross the lining of the mouth. The gum is available in strengths of 2 and 4 milligrams (mg), although the dose actually delivered to the chewer is 1 mg and 2 mg, respectively. Nicotine is absorbed from the gum gradually over 20 to 30 minutes, in the course of which nicotine levels similar to those seen after smoking a cigarette are produced in the blood. The gum is meant to be chewed intermittently, to allow time for the nicotine in the saliva to be absorbed. One should not chew the gum while drinking coffee, fruit juice, or cola drinks, because these beverages, by making the mouth more acidic, reduce the absorption of nicotine from the gum. Smokers are instructed to quit smoking and then to chew the gum regularly throughout the day, and also whenever they have the urge to smoke a cigarette. For maximum efficacy, nicotine gum should not be chewed within 10 minutes of drinking any beverage. Most people need to chew 8 to 10 pieces per day to obtain optimal benefits. Usually they chew the gum for 3 to 6 months but need to chew fewer pieces during the last couple of months. Side effects from chewing nicotine gum may include fatigue and soreness of the jaw, loosening of dental fillings, and occasionally nausea, indigestion, gas, or hiccups, particularly if one has chewed the gum so rapidly as to swallow nicotine-rich saliva.

Nicotine Patches.

To make it easier to stop smoking, researchers developed patches that administer nicotine without the side effects of nicotine chewing gum. Patches deliver nicotine in its un-ionized (uncharged) chemical form, thereby allowing the drug to pass through the skin readily. Various patches deliver different doses and are applied to the skin once a day, for times that range from sixteen to twenty-four hours. Four patches were available as of 1994 in the United States: Habitrol (Ciba-Geigy), Nicoderm (Marion-Merrell Dow), Nicotrol (McNeil), and Prostep (Lederle). All of these are available as over-the-counter medications. The patches deliver nicotine doses that are equivalent to smoking fifteen to twenty cigarettes (one pack) per day. Higher-dose patches are used during the initial three months of quitting, and lower-dose patches are available for subsequent tapering. Smokers who want to quit are instructed to first stop smoking and then to apply the patch daily. The usually minor side effects from nicotine patches may include itching or burning over the patch site, which usually subsides within an hour, and local redness and mild swelling. Some people experience a sense of stimulation and, occasionally, insomnia; with sleep may come vivid dreams. These effects tend to occur during the first few days of patch use but not thereafter.

Nicotine Nasal Spray.

The nicotine nasal spray was designed as a more rapid means of delivering nicotine to the smoker than the gum or the patch. The nasal spray consists of a small bottle containing a 10-mg/ml nicotine solution. A 50-milliliter spray containing 0.5 mg nicotine can be conveniently delivered using an accompanying manual pump. Each dose consists of two squirts, one to each nostril. This mechanism can deliver nicotine to the brain within 10 minutes, providing the most rapid nicotine delivery among the currently available nicotine replacement delivery systems. Patients are advised to use one or two doses per hour and may increase as needed. The minimum treatment is 8 doses per day, with a maximum limit of 40 doses per day (5 doses per hour). The side effects associated with the nasal spray are nasal irritation and throat irritation, sneezing, coughing, and teary eyes. These symptoms often occur during the first week of use but typically decline with continued use.

Nicotine Inhaler.

The nicotine inhaler consists of a plastic tube-like mouthpiece into which is placed a cartridge containing a nicotine-impregnated plug. Nicotine vapor is produced when warm inhaled air passes through the plug and nicotine is delivered through the buccal mucosa. The inhaler produces a rate of nicotine delivery similar to the nicotine gum. Dose is related to temperature, consequently, low temperatures will inhibit the release of nicotine. Clinical trials of the nicotine inhaler have shown that it produces double quit rates compared with placebo, similar to the effects observed with the three other nicotine replacement systems. Side effects from the inhaler include mild mouth and throat irritation, coughing, and runny nose. The frequency and severity of these symptoms decline with continued use of the inhaler.

Bupropion.

Bupropion sustained release (SR) is a non-nicotine medication that ranks as a first-line form of treatment. It is available by prescription only. Bupropion was originally marketed as an antidepressant, Wellbutrin. On the strength of evidence from several placebo-controlled trials, the FDA approved the marketing of bupropion (SR), under the trade name Zyban, as a treatment aid for smoking cessation. The mechanism by which bupropion assists smokers is not clear but it is thought to be related to both noradrenergic and dopaminergic activity. Patients are advised to begin using bupropion with a dose of 150 mg per day for three days, then to increase to 150 mg twice a day for one to two weeks prior to a selected day, with continued treatment for up to seven to twelve weeks following the quit date. Bupropion has been shown to reduce withdrawal symptoms and to reduce the weight gain usually associated with stopping smoking. The most common side effects reported by bupropion users have been insomnia and dry mouth. Bupropion is contraindicated in persons with a history of seizures, or of eating disorders, and those who have used a monoamine oxidase inhibitor in the past 14 days.

Clonidine.

Clonidine is an alpha2-noradrenergic agonist that was initially used for the treatment of hypertension, and subsequently found to diminish symptoms of both opiate and alcohol withdrawal. The efficacy of clonidine as a short-term smoking cessation aid was demonstrated in several studies in which clonidine was delivered either orally or in patch form. This drug has not received FDA approval as a smoking cessation aid, however, and should be considered a second-line treatment when first-line pharmacotherapies have not been successful. Clonidine use is associated with reductions in pulse rate and blood pressure, and abrupt discontinuation could result in a rapid rise in blood pressure and catecholamine levels. Side effects reported with clonidine use include dry mouth, drowsiness, dizziness, and sedation. Appropriate dose levels have not been established.

Nortriptyline.

Nortriptyline is used primarily as an antidepressant (Pamelor) and has not been evaluated or approved by the FDA for the treatment of tobacco dependence. Increased abstinence rates with notriptyline use, compared with placebo, were observed in two controlled trials. In those smoking cessation trials, nortriptyline use was initiated at a dose of 25 mg/day, and increased gradually to 75 to 100 mg per day over 12 weeks. Sedation, dry mouth, blurred vision, urinary retention, lightheadedness, and shaky hands are the most commonly reported side effects of nortriptyline use. Nortriptyline may also cause cardiovascular changes. This side effect profile and the need for evidence from more controlled studies consigns nortriptyline to the status of a second-line smoking cessation aid at the present time.

Other treatments.

A number of other treatments are available or have been used in the past to aid in smoking cessation. Although the effectiveness of these treatments has not been established by medical research, some individuals may benefit from them. None of these treatments, however, can magically cure smokers of their tobacco addiction without the commitment and effort that are usually required to quit.

Hypnosis

has been widely used to increase a smoker's motivation or commitment to stop. While under hypnosis, the smoker receives suggestions, such as "smoking is a poison to your body," "you need your body to live," "you owe your body respect and protection." This treatment probably works best in combination with the previously discussed behavioral modification programs.

Acupuncture

as a smoking-cessation technique involves the placement of needles or staples in various parts of the body, most commonly the ears. Although acupuncture may be helpful for some smokers, a meta-analysis did not support the efficacy of this form of treatment.

Lobeline and silver acetate

medications have been available in pharmacies without a physician's prescription. Lobeline, a chemical similar to nicotine but with less psychoactivity, has been recently removed from the market by the Food and Drug Administration. Lobeline has been available in prescriptions such as CigArrest, Bantron, and Nikoban. Silver acetate, available in a chewing gum, mouthwash, mouth spray and lozenges, acts as a deterrent. Tobacco smoke combines with the silver in the mouth to precipitate silver sulfide, which has an unpleasant taste. The unpleasant taste presumably decreases the incidence of smoking.

TREATMENT OF SMOKELESS TOBACCO ADDICTION

Much evidence indicates that the use of smokeless tobacco produces addiction and leads to serious health consequences as does the use of smoked tobacco. However, little is known about effective treatment for smokeless tobacco (i.e., snuff or chewing tobacco) addiction. The general behavioral approach is similar to that for cigarette smoking, although the specific learned associations and cues are naturally somewhat different. Self-help materials are available from a variety of sources in the United States. Some strategies include the use of alternative activities, such as chewing gum, hard candy, sunflower seeds, nuts, toothpicks, or beef jerky. Formal treatment programs are also available in some parts of the country. At the present time, insufficient evidence exists to suggest that the use of established medications designed for helping cigarette smokers increases long-term cessation among users of smokeless tobacco.

(See also: Addiction: Concepts and Definitions ; Relapse Prevention ; Tobacco Smoking Cessation and Weight Gain ; Treatment )

BIBLIOGRAPHY

United States Department of Health and Human Services. (2000). Treating tobacco use and dependence. Clinical Practice Guidelines. Chapter 6. Evidence, 49-89.

Neal L. Benowitz

Alice B. Fredericks

Revised by Lirio S. Covey