Causes and Symptoms (Magill’s Medical Guide, Sixth Edition)
Nicotine is an addictive substance found in cigarettes, cigars, and chewing snuff. Nicotine dependence is a diagnosis given to a person who continues to use the drug despite negative consequences resulting from its use. Problems can include tolerance, withdrawal, uncontrolled use, unsuccessful efforts to quit, considerable time spent getting or using the drug, a decrease in other important activities because of use, and health problems caused or worsened by use. These health problems include cardiovascular problems, such as blood clots, high blood pressure, and strokes; cancers of the bladder, head, lungs, neck, pancreas, and throat; and chronic lung problems, such as emphysema. Studies have shown lower birth weight in the babies of mothers who smoke; higher rates of allergies, asthma, bronchitis, and colds in children of parents who smoke; and higher death rates from cancer in individuals regularly exposed to secondhand smoke.
(The entire section is 142 words.)
Treatment and Therapy (Magill’s Medical Guide, Sixth Edition)
In primary prevention, an entire population is provided with a form of treatment. Examples are antismoking campaigns focused on the dangers of smoking. Laws prohibiting individuals from smoking in airplanes are also a good example of primary prevention. In secondary prevention, interventions are applied to individuals at greater-than-average risk for smoking. Children of smokers would be such a group. An appropriate intervention might be giving these children health information to encourage them to avoid starting tobacco use. In smoking cessation programs, also known as tertiary prevention, people with nicotine dependence are provided with self-help materials or the use of professional services. With professional service providers, interventions may include combinations of treatments such as nicotine replacement patches, nicotine gum, prescription drugs, and psychological therapy.
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Perspective and Prospects (Magill’s Medical Guide, Sixth Edition)
Nicotine was identified chemically in the nineteenth century, but tobacco had been used by Native Americans to celebrate religious rituals and sacred rites for many years. In contrast, in contemporary society, the use of nicotine is habitual and seldom attached to rituals of religious significance. From 1970 to 2000, smoking rates decreased in the United States. It appears, however, that this decline was more apparent in men than in women. As such, it is likely that treatment and prevention approaches will need to address such gender differences.
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For Further Information: (Magill’s Medical Guide, Sixth Edition)
Carlson-Berne, Emma, ed. Nicotine. Detroit: Greenhaven Press/Thomson Gale, 2006.
Dodgen, Charles E. Nicotine Dependence: Understanding and Applying the Most Effective Treatment Interventions. Washington, D.C.: American Psychological Association, 2005.
George, Tony P., ed. Medication Treatments for Nicotine Dependence. Boca Raton, Fla.: CRC/Taylor & Francis, 2007.
Julien, Robert M. A Primer of Drug Action: A Concise, Nontechnical Guide to the Actions, Uses, and Side Effects of Psychoactive Drugs. 11th ed. New York: Freeman, 2008.
Kozlowski, Lynn T., Jack E. Henningfield, and Janet Brigham. Cigarettes, Nicotine, and Health: A Biobehavioral Approach. Thousand Oaks, Calif.: Sage Publications, 2001.
Weil, Andrew, and Winifred Rosen. From Chocolate to Morphine: Everything You Need to Know About Mind-Altering Drugs. Rev. ed. Boston: Houghton Mifflin, 2004.
(The entire section is 114 words.)
Nicotine (Encyclopedia of Drugs and Addictive Substances)
- How Is It Taken?
- Are There Any Medical Reasons for Taking This Substance?
- Charley, the Addicted Chimp
- Reactions with Other Drugs or Substances
- Nicotine Withdrawal Symptoms
- Kreteks and Bidis
- For More Information
What Kind of Drug Is It?
Nicotine is the ingredient in tobacco that causes changes to the brain and behavior. Tobacco, a broad-leafed plant that originated in the Americas, is one of the most widely abused , or mind-altering, substances in the world. In the United States alone, one in four men and one in five women smoke cigarettes, cigars, pipes, or use oral products such as chewing tobacco or snuff. In other parts of the world the percentage of users is even higher.
Nicotine use typically begins among Americans between the ages of eleven and eighteenn age group too young to buy the product legally. Young users soon discover that nicotine is habit-forming, that all the ways of taking it pose great health risks, and that it can lead to troubles on the job and sometimes an early death.
Movies and tobacco advertisements present nicotine use as a glamorous, rebellious, adult activity. And adults can smoke legally. What the advertisements do not note, however, is the fact that one-third of all smokers live below the poverty level; that the more educated a person is, the less likely he or she is to use tobacco; and that an estimated one billion people will die from tobaccorelated illnesses worldwide in the twenty-first century. Tobacco use is one of the leading causes of preventable death. Its link to cancerOut-of-control cell growth leading to tumors in the body's organs or tissues., emphysema and asthma (lung disorders), and depression (a mood disorder), has been clearly established. Smokers can expect to live seven to ten years less than people who do not use tobacco products.
At the height of tobacco's popularity in the United States in the 1960s, more than half of all adult men and about one in three adult women smoked cigarettes. People smoked in movie theaters and on buses and planes. They smoked at their desks in office buildings and in their beds at night. Famous film and television stars promoted certain brands of cigarettes in commercials and on billboards. Even in those times, however, people knew that smoking could ruin their health.
A half-century later, in the early 2000s, smokers can find it difficult to get a job if they reveal a tobacco habit. Smoking is not permitted on planes, in theaters, in many office buildings, or on public transportation. Many cities have enacted bans on smoking in restaurants and bars.
Studies have proven that , or "passive" smoke, can cause many health problems for the nonsmoker. Pregnant women who smoke endanger the health of their unborn babies. Most Americans are less tolerant of smoking than they used to be. Yet, the "2003 National Survey on Drug Use and Health (NSDUH)" reported that 40 percent of young adults age eighteen to twenty-five admitted to smoking cigarettes at least once in their lives.
No country that has learned to use tobacco has ever given it up. Nicotine addiction, a physical dependence on the drug due
to repeated drug use, continues to be a global public health issue. It is one of the leading causes of preventable illness in adults. The U.S. government keeps a watchful eye on tobacco companies to ensure they do not target cigarette advertisements to teens for several reasons. First, teens are not allowed to smoke legally. Second, adults over the age of twenty-five rarelyf everegin smoking after never having smoked before.
The first European to record seeing tobacco use was the explorer Christopher Columbus (1451506), in 1492. On his initial voyage to the New World, Columbus wrote in his diary that the native peoples he encountered "drank" smoke from the burning leaves of a certain plant. Even without understanding their language, Columbus could see that the people he met highly valued their tobacco.
Use Originated in the Americas
Archaeologists are not sure where or when tobacco use began in the Americas. More than sixty varieties of tobacco grew all over North and South America. Even the garden flower known as the petunia is related to tobacco. The earliest documented use of tobacco among Native Americans occurred with the Mayan culture, a civilization from Central America that peaked about 2,000 years ago. A carving on a Mayan temple shows an elaborately dressed man smoking a long-stemmed pipe. Other historians of ancient America believe that pipe smoking may have begun in North America and spread south. Whatever the case, by 1000 CE, most Native American cultures used tobacco in religious and political rituals. The plant did not grow in Europe.
Columbus and his crew were baffled and disturbed by the sight of people smoking tobacco. Nevertheless, they collected specimens of the plant, as well as pipes, and took them back to Spain. As the Spanish and Portuguese began to explore and settle the Americas, they began "drinking smoke" themselves. Sailors who moved between Europe and America were among the first to discover that once they began smoking tobacco, they could not stop.
By 1535, Spanish colonists in the New World were planting tobacco for their own use. At around the same time, farmers in Europe began to cultivate the plant. In 1559, the French ambassador to Portugal, Jean Nicot (1530600), became interested in tobacco. He thought it might be useful as a medicine. He introduced powdered tobaccoi>snufft the French court and made the substance fashionable. It is from his name, "Nicot," that the word nicotine is derived.
Tobacco in the American Colonies
Tobacco was one of the first crops planted when English colonists arrived in Jamestown, Virginia. Ships filled with tobacco sailed from America to Europe, where the tobacco was traded for items the colonists could not make or buy in the New World, including tea, furniture, and high-quality cloth. In some parts of America, tobacco could be used instead of money. The need for new fields to grow tobacco plant that uses up the rich nutrients in the groundushed settlers westward, into territories occupied by Native Americans. By the time the Declaration of Independence was signed in 1776, tobacco smoking was common in America. Every tavern kept a supply of clay pipes for use by visitors. When smokers were finished with their pipes, they broke off the part of the stems their lips had touched and passed the pipe to a new user.
By the nineteenth century, different classes of people used tobacco in different ways. The upper classes tended to "take snuff," inhaling powdered tobacco through the nose. The middle classes preferred pipes, and the lower classes held wads of tobacco between their gums and teeth, a practice known as "chewing." Within 300 years of its discovery by Columbus, tobacco had spread to all parts of the world. Many cultures considered it a beneficial medicine. The Native Americans had wrapped shredded tobacco in larger leaves, and "cigars" became popular by the turn of the twentieth century. "Cigarettes" were invented by people who gathered the shredded cigar tobacco that had gone to waste and wrapped it in small papers to smoke it.
The popularity of cigarettes skyrocketed during World War I (1914918), because they were easy to transport into battle. Many young soldiers brought the cigarette habit home with them, and factories stood ready to create the product on assembly lines. By the 1920s, whole industries built on tobacco advertised in print, on billboards, and through movies and radio. Women were encouraged to smoke, and they took up the habit as well. The "Jazz Era" generation was the first to embrace tobacco in great numbers. The era's great athletes smoked when not on the playing field and chewed tobacco during games. During the Great Depression (1929941), U.S. President Franklin Delano Roosevelt (1882945) was sometimes photographed with a cigarette, in a holder, in his mouth.
Tobacco-Related Illness Begin to Surface
Americans who had been young in the 1920s were entering their sixties by the 1960s. At that time, tobacco use began to show its downside. Even as new generations became hooked on nicotine, older Americans suffered increasing numbers of lung, throat, and mouth cancers. Others died of emphysema, a disorder that affects the lungs' ability to process oxygen. In 1961 the Surgeon General of the United States requested a report on the effects of tobacco use on health. Facing opposition from tobacco companiesho claimed to have done their own research panel of experts met to study the problem.
In 1964 the panel submitted a report to the Surgeon General that linked tobacco use to lung cancer, mouth and throat cancer, heart attacks, , emphysema, and other diseases of the stomach and liver. The report, to no one's surprise, declared that nicotine was habit-forming. At the time the report was issued, 40 percent of adult Americans used some form of tobacco.
By the late 1960s, nonprofit groups from many sectors were uniting to stop tobacco use in the United States. Groups such as the American Heart Association, the American Lung Association, and the American Cancer Society launched advertisements to counter the popular characters featured in cigarette ads, including Joe Camel and the Marlboro Man. Perhaps just as effective for younger people was the personal experience of a loved one parent, a grandparent, or an older siblinguffering the ill effects of tobacco use. Smoking declined among the American public as a result.
The terms passive smokingInhaling smoke from someone else's burning cigarette. and "secondhand smoke" had not been invented in the 1960s. However, by the 1990s people had become aware that tobacco smoke posed a threat not only to the smoker, but also to those exposed to the smoldering cigarette or cigar, and the exhaled smoke. Private companies began to ban smoking in office buildings, and a whole series of laws followed, banning smoking in public transportation, on airplanes, in health care facilities, and in government buildings. People who had once puffed at their desks were forced to smoke on their breaks, huddled outside in all sorts of weather. At the same time, states began to levy higher taxes on cigarettes to help pay for Medicaid and other social welfare programs.
Tighter Laws Cut Down on Nicotine Abuse
On November 16, 1998, forty-seven states and the District of Columbia came to an out-of-court settlement with four major American tobacco companies. (The other three states had previously come to agreements.) The states had sued the tobacco companies for the costs of providing health care to poor people suffering from tobacco-related illnesses. The cigarette companies agreed to pay the states $206 billion for health care. The companies also agreed not to market their product to adolescents through advertisements or promotional items. They further agreed to fund a program to discourage teenage smoking. One consequence of this settlement: The average price of a pack of cigarettes rose fifty cents in one year, from $2.20 in 1998 to $2.70 in 1999. By 2005, cigarettes were selling for about $4.00 per pack. For heavy smokers, many of them poor already, this was a difficult increase to manage.
Despite the successes made in the anti-tobacco campaign, smoking still appealed to youth who wanted to rebel against authority. In fact, by suggesting that tobacco was something that only adults should use just made it more popular with rebellious youth who wanted to seem hip and mature. Smoking was also glamorized in various movies as something that cool people do. As of the early twenty-first century, a large number of teens still take up smoking. The National Center for Chronic Disease Prevention and Health Promotion estimates that about 4,000 people under the age of eighteen begin smoking each day in the United States.
More recently, the healthcare industry has focused on smoking in films. "Product placement" is very important in movies. When a character in a film uses a particular food or beverage product, sales of that product often climb. In 2005 the American Medical Association recommended that the film industry adopt a policy that would automatically give an "R" rating to any movie in which a character uses tobacco. (People under seventeen are not supposed to be admitted to "R" rated movies without a parent or adult.) Whether the film industry will honor that request is uncertain.
What Is It Made Of?
Nicotine is a poisonous that occurs naturally in the leaves of the tobacco plant. While still in the leaves of the plant, it is a colorless liquid. Sixty milligrams of nicotine, about the amount
a bottle cap would hold, can kill a human being. It is used as a pesticide to kill insects on plants and internal parasites in animals.
The chemical formula for nicotine is C10H14N2. Theaverage cigarette contains 8 to 10 milligrams of nicotine, but much of this is lost in the process of burning. Typically, a smoker receives about 1 milligram of nicotine per cigarette. A pinch of chewing tobacco contains between 4.5 and 6.5 milligrams of nicotine. Since chewing tobacco enters the body more slowly than smoked tobacco, more of the dose is absorbed, but over a longer period of time.
In addition to nicotine, a smoking leaf of tobacco releases more than 4,000 different chemicals. Four hundred of these are known to be poisonous, and forty-three have been shown to cause cancer. A lit cigarette releases, among other things, carbon monoxideA poisonous gas with no odor; carbon monoxide is released when cigarettes burn., ammonia, hydrogen cyanide, benzene, formaldehyde, acetone, methanol, and vinyl chloride. Tobacco companies add other ingredients to cigarettes as well, including menthol. Menthol numbs the throat to the irritating effects of the smoke. It also widens the pathways in the lungs, allowing more smoke to penetrate the tissues.
When smoke is exhaled from the lungs, a substance called tar remains in the body. As its name suggests, tar is a sticky residue that clings to lung tissue. Tar contains cancer-causing compounds. Receiving nicotine through the mouth by chewing reduces some of the dangerous chemicals from tar, but it also exposes the tissues in the mouth to cancer-causing agents and compounds that cause tooth decay and gum disease. The same compounds in tar simply cling to the mouth tissues and are absorbed by the gums, cheeks, and throat.
How Is It Taken?
Nicotine is taken in several ways. The most common and quick-acting manner is smoking. The user lights a cigarette, draws the smoke into the lungs, and exhales it. The effects of the nicotine can be felt within ten seconds, and they usually last between fifteen minutes and an hour.
People who smoke cigars and pipes generally "puff" them and do not inhale the smoke into the lungs. Even so, the soft tissues in the mouth absorb the nicotine and send it through the bloodstream to the brain. Smoking pipes or cigars is, indeed, habit-forming. Puffing is just another way to deliver nicotine to the brain. The presence of the smoke in the mouth and throat can lead to cancers in those body parts, and to cancer of the esophagus, the tube leading into the stomach.
With chewing tobacco, the user takes a wad of moist tobacco and presses it between the cheek and the gum. As the mouth fills with saliva, the user must spit, because swallowing tobacco-laced saliva could be deadly and certainly causes stomach upset. Users of chewing tobacco generally keep a wad in the mouth for about thirty minutes, during which time about 2 milligrams of nicotine enter the bloodstream through the cheek and gum tissue.
Few people snort snuff anymore, but it was once a popular way to use nicotine. Snuff, finely-ground tobacco, was snorted up the nose and usually removed by sneezing. A "pinch of snuff" was thought to ward off colds and other infectious diseases.
Are There Any Medical Reasons for Taking This Substance?
Some small studies have been performed to see if nicotine patches help reduce memory loss in patients and muscle tremors in Parkinson's diseaseAn incurable nervous disorder that worsens with time and occurs most often after the age of fifty; it is generally caused by a loss of dopamine-producing brain cells; symptoms include overall weakness, partial paralysis of the face, trembling hands, and a slowed, shuffling walk. patients. Since nicotine is so highly addictive, however, its valid medical uses are considered very minimal.
The only acceptable medical use for nicotine is to help people overcome addiction to nicotine. "Nicotine delivery systems" include skin patches, gum, inhalers, and nasal sprays. Tobacco users trying to quit the habit can curb nicotine's symptoms with these products. The products become very dangerous if a person smokes while using them. In that case, nicotine overdose is possible. Although some nicotine replacement products are available over the counter, most encourage nicotine addicts to seek the advice and counsel of a medical doctor while attempting to curb nicotine use.
The American Heart Association Web site posts data on patterns of tobacco use among adults age eighteen and older in the United States. As of 2002, 25.2 percent of white American men and 20.7 percent of white American women used tobacco. In 2002, 27 percent of African American men and 18.5 percent of African American women used tobacco. Hispanic/Latino men reported 23.2 percent usage, and Hispanic/Latino women, 12.5 percent. Asian Americans were the least likely to use tobacco, with 21.3 percent of men and 6.9 of women reporting usage. The population most likely to use
tobacco, according to the American Heart Association data, is Native Americans/Alaskan Natives, who reported that 32 percent of adult men and 36.9 percent of adult women were tobacco users. The numbers add up to 47.5 million adult American users.
What the Surveys Say
The 2003 NSDUH found 70.8 million tobacco users in the United States, factoring in anyone over the age of twelve who had ever tried tobacco. Of these, the NSDUH characterized 35.7 million as nicotine addicts. This number includes Americans age twelve and older. The NSDUH data on teenage nicotine use does not break down by race or ethnic origin, reporting simply that 12.5 percent of girls age twelve to eighteen use tobacco, along with 11.9 percent of boys. These rates are down from previous years.
Incidents of tobacco use seem to peak between the ages of eighteen and twenty-five, when, according to the NSDUH, 40.8 percent of people report at least one experience with the product. The data clearly show that most Americans begin using tobacco products between the ages of twelve and twenty-five. It is this "target audience" that the anti-smoking campaigns seek to educate about the health dangers of tobacco. According to various anti-smoking organizations, it is this same group that smoking advertisements target.
Although the number of young smokers remains high, data from the 2004 Monitoring the Future (MTF) study show a slow but steady drop in the percentage of eighth-, tenth-, and twelfth-grade students who smoke cigarettes. Back in 1996, 21 percent of eighth graders, 30.4 percent of tenth graders, and 34 percent of twelfth graders had smoked during the month prior to the survey. Eight years later, in 2004, the figures had fallen to 9.2 percent of eighth graders, 16 percent of tenth graders, and 25 percent of twelfth graders reporting past-month cigarette usage. Teens who said they smoked more than a half a pack of cigarettes daily fell significantly over the eight-year span as well. In addition, according to MTF survey authors, "the perception of harm from smoking one or more packs per day increased significantly among eighth- and tenth-graders from 2003 to 2004."
Ties to Social Problems?
The various surveys show another fact as well. According to the American Heart Association, people with a high school education or less are three times more likely to be smokers than those with a college education. The prevalence of cigarette smoking is highest among people living below the poverty level, with one in three reporting tobacco use.
A study of more than 4,000 students in Oregon and California linked early smoking with problem behaviors. Kids who start smoking around age twelve are considered "early smokers." In an article published in the Journal of Adolescent Health, Phyllis L. Ellickson and her coauthors reached the following conclusion: "Compared with nonsmokers, early smokers were at least three times more likely by grade twelve to regularly use tobacco and marijuana, use hard drugs, [and] drop out of school." In addition, these adolescents were "at higher risk for low academic achievement and behavioral problems at school."
Effects on the Body
Nicotine is the addictive compound in tobacco. When it enters the bloodstream, either through the lungs, the skin inside the mouth, or the nasal passages, it moves to the brain. There it binds with receptors, triggering the release of other neurotransmittersA substance that helps spread nerve impulses from one nerve cell to another. and hormones. Basically, nicotine causes two sensations: stimulation in the thought processes, and general relaxation in the user.
The Need for a Cigarette
The quick-acting nicotine increases the amount of in the brain. This causes pleasure and relaxation of muscles. At the same time, it enhances norepinephrinePronounced nor-epp-ih-NEFF-run; a natural stimulant produced by the human body. and acetylcholine levels, increasing mental stimulation and suppressing appetite. Nicotine also enhances memory and promotes a feeling of well-being. In other words, the drug stimulates the brain's reward system, making the user "feel good."
When people say that cigarettes help them to concentrate, they are not exaggerating. Nicotine does have that effect. However, the effect wears off quickly unless another dose of nicotine enters the brain. Likewise, nicotine does cause a feeling of relaxation, but this too passes quickly, leading to a craving for more of the drug. Many behaviors are related to the addicting qualities of nicotine. The user, taking a puff on a cigarette, might just feel more relaxed because withdrawal symptoms have been held at bay for another hour.
A Dangerous Habit
Nicotine causes a release of , leading to a faster heartbeat, higher blood pressure, quickened breathing, and higher blood sugar. So while the user may feel relaxed, the body is actually working harder to pump blood and take in oxygen. Over a long period of time, this strain on the heart and elevated blood pressure can lead to heart attack and stroke. The drug also complicates the chemistry of the blood, causing blood vessels to become smaller and blood cells to stick together in clots. This can increase the risk of organ damage and stroke. Over time, nicotine contributes to the build-up of plaque in the arteries, a leading cause of heart disease. The chemicals in cigarette smoke also irritate the throat, interfere with the lung's ability to clear debris and bacteria, and promote nausea and other digestive disturbances.
Most scientists agree that nicotine is the most addictive substance used by humankindorse than cocaine, although it works in a similar way on the brain's reward centers. (An entry for
cocaine is available in this encyclopedia.) Because nicotine works so quickly and exits the brain just as quickly, it begins to induce cravings in most users within days or weeks of first use. Its effects are particularly strong on those with attention-deficit/hyperactivity disorder (ADHD), for whom it may be calming, and those with depression or a tendency to become depressed. People with those problems have a harder time freeing themselves from a nicotine addiction, so they are advised not to use tobacco at all.
Regular tobacco use causes toleranceA condition in which higher and higher doses of a drug are needed to produce the original effect or high experienced., a condition that can lead to heavy smoking or chewing, and to lifestyle changes based on that heavy use. People find themselves spending a great deal of money on tobacco products, using them recklessly (smoking in bed, smoking while driving), and endangering the health of others with secondhand smoke.
At overdose levels, nicotine causes dizziness, vomiting, muscle tremors, convulsions, and paralysis of the lungs leading to an inability to breathe. All of these symptoms can develop within minutes. Tobacco products should be kept out of reach of children and pets. Those using nicotine replacement products should never smoke or chew tobacco at the same time. In addition, great care should be taken with any insecticide or other product containing pure nicotine.
The immediate effects of nicotine are generally mild and pleasurable; the long-term effects of tobacco use are not. Smokers accumulate a huge buildup of tar in the lungs, promoting cancer and clogging the air sacs that transfer oxygen into the bloodstream. The cancer-causing chemicals in tobacco promote growth of tumors in the mouth, on the lips, in the throat, in the lungs, in the esophagus, and elsewhere in the body. Nearly one in five deaths due to heart disease can be blamed on tobacco, and the overall death rate from cancer is twice as high among smokers as among nonsmokers.
People who smoke damage tiny, hair-like structures called cilia that lead to the lungs. Cilia help to remove germs and dirt from the lungs. This leads to an accumulation of mucus in the lungs and bronchial tubeshe famous "smoker's cough." Smokers also suffer more frequent and more serious cases of flu and pneumonia. Heavy tobacco use can cause men to become impotent and their sperm counts to decrease. Tobacco use has also been linked to cancers in the female reproductive organs.
Perhaps the most dangerous aspect of nicotine is the time it takes for the deadly side effects to develop. Most people begin using tobacco as teenagers, a time when they are most vulnerable to peer pressure and subtle advertising techniques. The vast majority of teenagers are enjoying the best health they will ever have in their lives. They cannot imagine growing old, developing health problems, or being at risk for fatal diseases. By the time they begin to understand how fragile the body is, they can already be deeply dependent on nicotine.
Becoming free of nicotine addiction causes immediate and long-term health benefits, including improved breathing, better sensation of taste, healthier teeth and skin, and improved strength. Quitting smoking also lessens the risks of cancerut not entirely. Sometimes people who have not smoked in years discover that they have lung cancer. The disease is difficult to diagnose in its early stages. The very best way to avoid nicotine-related illnesses is to avoid any use of nicotine at any stage of life. If nicotine use has begun, the sooner it ends, the better the chances of living a long and healthy life.
Reactions with Other Drugs or Substances
Tobacco use causes the liver to produce more enzymes that can lower the blood levels of other medicines. Doctors should alter the doses of prescription drugs and monitor patients more carefully if those patients are using tobacco or nicotine replacement products. Nicotine should not be combined with certain asthma drugs, blood thinners, antipsychotic drugs, drugs for migraine headaches, and some antidepressants. Nicotine also interferes with some blood pressure medications such as Procardia and Tenormin. Women who are using birth control pills are urged not to smoke, because the combination of the pills and the tobacco can increase the likelihood of blood clots.
Any combination of nicotine and cocaine, opiates, hallucinogens, or marijuana can heighten the effects of the illegal drugs and possibly lead to irregular heartbeat or breathing problems. Heavy use of tobacco and alcohol further increases cancer risks. (Entries on alcohol and marijuana are available in this encyclopedia.)
Treatment for Habitual Users
Giving up the nicotine habit can be very difficult. Within hours of the last cigarette or chew, the body begins to respond to the lack of the drug. People become irritable and anxious, they overeat, they cannot sleep, and they can experience muscle tremors and a craving for tobacco. Many times, it is just easier to get another cigarette rather than to face the withdrawal symptoms.
Many self-help groups, including Nicotine Anonymous, the American Lung Association, the American Cancer Society, and the National Cancer Institute, have smoking cessation, or stopping, programs. Local- and state-funded programs also provide counselors and various treatment methods to the motivated addict who wants to quit using tobacco. These treatment programs may use hypnosis, group therapy, or behavior modification to encourage alternate behavior and help individuals combat the many facets of nicotine addiction. In many cases, health insurance companies will help pay for nicotine treatment programs.
Probably the most successful treatment methods involve nicotine replacement products such as gum (Nicorette) and skin patches (NicoDerm CQ, Nicotrol, Habitrol, and ProStep). These products recommend that the user work closely with a doctor or therapist to taper the doses of nicotine slowly. People using nicotine replacement therapies must take care not to use tobacco products at the same time, since this may lead to nicotine overdose. They must also be aware that these therapies can be habit-forming themselves, so they must be motivated not to exceed the recommended dose on the label of the package.
Other prescription drugs used to curb nicotine abuse include buproprion (Zyban), an antidepressant, and Clonidine (Catapres), a medicine to reduce high blood pressure. Both of these products block nicotine's pleasurable effects and help a recovering user avoid tobacco products.
For most, the best way to treat a tobacco habit is to combine a nicotine replacement therapy with counseling, education, group support, and the encouragement of family and friends. A heavy tobacco user must expect that the process will not always go smoothly and must have strategies in place for times of stress. Recovering nicotine addicts usually need to alter their lifestyles in order to avoid the people and places associated with smoking. If other family members smoke in the home, this can be very challenging.
The least effective way to attempt to quit nicotine is to depend on will power or to attempt to cut back on smoking by using low-tar cigarettes or by smoking less. People who try to quit in this way usually compensate by drawing more deeply on the cigarettes they do smoke. The relapse rate for this type of cessation is very high.
Nicotine erodes health slowly at first. Most people begin smoking early in life, when they are enjoying the best health they will ever have. Gradually, however, the consequences of long-term tobacco use become evident. People suffer from bad breath, discolored teeth, cravings, and dryness and thinning of the skin. They may develop a "smoker's cough" or a gravelly voice from damage to the larynx, the organ that produces sound in the throat. They may develop lesionsores that do not heal or that heal very slowlyn their lips or inside the mouth. All of these are early warning signs of trouble to come.
Increased Risk of Cancer and Other Illnesses
It is estimated that one-third of all cancers and 87 percent of lung cancer in the United States can be traced directly to tobacco use. Cancer
is an illness in which cells grow and reproduce too quickly, causing tumors inside the body. The tumors can be small at first and then grow rapidly. If the cancer reaches the lymph glands that send hormones throughout the body, the cancer can spread through the body as well. Cancer treatment generally involves surgery to remove tumors. Surgery is often followed by chemotherapy, a process that shrinks tumors but also causes nausea, weakness, hair loss, and malfunction of the immune system. Some tumors are treated with radiation to stem their growth. Radiation can cause pain and burning of the skin.
Cancer is treatable, but smokers are twice as likely to die of it as nonsmokers diagnosed with the same illness. Heavy smokers are four times more likely to die of their cancers as nonsmokers diagnosed with similar cancers.
Long-term tobacco use is directly linked to heart attack, various lung illnesses, high blood pressure, and stomach ulcers. It also reduces the body's ability to heal broken bones, promotes arthritis, and causes bad breath and yellowing of the teeth. All of these effects stem from a product that is legal for use in the American adult population. However, the U.S. Surgeon General's warning about the various health consequences of smoking appears on all packs of cigarettes sold in the United States.
In most states, people must be eighteen years old to purchase tobacco products legally. In Alabama, Alaska, and Utah, the minimum age for purchase of tobacco is nineteen. As of the early 2000s, four other statesalifornia, New Jersey, Illinois, and Massachusettsere considering laws to raise the age as well. The burden of keeping underage persons from buying cigarettes or smokeless tobacco falls on the stores that sell it.
Shopkeepers risk prosecution if they are caught selling tobacco to minors. Most stores require that younger buyers produce valid identification showing date of birth. Occasionally, young undercover police officers will attempt to buy tobacco without proper identification to see if the shopkeepers are abiding by the law. A store owner who sells tobacco to a minor risks losing his or her license to sell the product, as well as fines or closure of the business.
People under the age of eighteen who get caught with tobacco products do not face criminal prosecution. However, they can be suspended from school if caught with tobacco on school grounds. Most authorities contact parents or legal guardians to report the situation. For teens who smoke, secrecy rarely lasts very long. The telltale smell of tobacco clinging to clothing and hair is hard to disguise.
Discrimination Against Smokers
In some states, private companies have introduced policies that deny jobs to smokers. The companies cite the extra burden of health care costs for their smoking employees, as well as loss of work time due to smoking breaks. Many smokers claim that this is discrimination and should not be a factor deciding employment, especially since smoking is legal. As of early 2005 no lawsuits had yet developed from the introduction of these measures, but analysts expected that legal action would soon occur.
Various states have laws that prohibit employers from discriminating against their staff for engaging in certain legal activities, like smoking, while they are not at work. According to Marshall H. Tanick in the Minneapolis Star Tribune "about two dozen states have so-called 'lifestyle rights' laws," including Minnesota, Texas, California, and Florida. Such laws prohibit employers from discriminating against "employees because of lawful off-duty conduct." Tanick noted that the 1992 Minnesota law specifically "extends to consumption of 'food, alcohol, or non-alcoholic beverages and tobacco."' Employers can restrict the use of certain products, consumed by the employee off-duty, if use of those products interferes with the person's ability to do his or her job.
For More Information
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See also: Alcohol; Cocaine; Marijuana
Nicotine (Encyclopedia of Drugs, Alcohol, and Addictive Behavior)
This is a PSYCHOACTIVE chemical substance found in TOBACCO products, including cigarettes, cigars, pipe tobacco, and smokeless tobacco such as chewing (spit) tobacco and oral and nasal SNUFF. The nicotine molecule is composed of a pyridine ring (a 6-membered nitrogen-containing ring) with a pyrrolidine ring (a 5-membered nitrogen-containing ring).
Nicotine can occur in two forms. The active form, called L-nicotine, is found in tobacco plants of the genus Nicotiana. These are chiefly South American plants of the nightshade family (Solanaceae)nnuals cultivated since pre-Columbian times for their leaves, especially Nicotiana tabacum. The inactive form, D-nicotine, is not present in tobacco leaves but is formed, to a small extent, in the combustion of tobacco during smoking. These two forms are stereoisomers, meaning that even though they are both nicotine, they have different three-dimensional structures. In pure form, nicotine is a colorless liquid, but it turns brown on exposure to air.
Nicotine is water-soluble and transfers from tobacco to cigarette smoke readily, because it vaporizes easily. Once it is in the body, conditions are ideal for rapid distribution to blood and tissues because nicotine is a weak base, and when un-ionized under alkaline conditions, such as those found in the blood stream, it crosses cell membranes easily.
The primary natural source of nicotine is the tobacco plant, but nicotine is also found in some amount in related plants. Small amounts are in foods of the nightshade family, such as tomatoes and eggplants. Consumption of nicotine has not been limited to the use of plants in which it naturally occurs. In 1828, the German scientists Posselt and Reiman isolated nicotine from tobacco leaves, and since then it has been added to other products. For example, it is widely used as an insecticide in such products as Black Leaf 40, which contains 40 percent nicotine sulfate.
EFFECTS OF NICOTINE
The first pharmacological studies of nicotine were initiated in 1843 by Orfila. Nicotine is an
Effects in the Body.
The actions of nicotine in a human body are complex. They depend on the amount of nicotine given, the route of administration (e.g., by mouth or intravenously), the time over which the dose is given, and the individual's history of exposure to nicotine. In high doses, nicotine produces nausea, vomiting, convulsions, muscle paralysis, cessation of breathing, coma, and circulatory collapse. Such high doses are seen after accidental absorption of a nicotine-containing insecticide or an overdose of nicotine.
In lower doses, such as those used by people who consume tobacco products, the effects are very different. They include a speed up in heart rate and blood pressure; increased force of contraction of the heart; constriction of blood vessels in the skin, producing cool, pale skin; constriction of blood vessels in the heart; relaxation of skeletal muscles; increased body metabolic rate; and the release of hormones such as epinephrine (adrenaline), NOREPINEPHRINE, and cortisol into the bloodstream. Nicotine's effects on the brain are very complex because nicotine works in part by enhancing the release of chemicals that transmit information from one neuron to another (NEUROTRANSMITTERS) by brain cells. For example, nicotine enhances the release of DOPAMINE, which may produce pleasure; norepinephrine, which may suppress appetite; acetylcholine, which produces arousal; SEROTONIN, which may reduce anxiety; and beta ENDORPHIN, which may reduce pain. The development of addiction to nicotine in tobacco users is attributed in part to many of the effects of nicotine that people find desirable.
Effects of Nicotine in Cells.
Nicotine binds (attaches) to RECEPTORS on cell membranes that normally bind a neurotransmitter called ACETYLCHOLINE. Acetylcholine, like other neurotransmitters, is a chemical released by nerve endings in the body that binds to certain receptors on cells and activates them. The activated cells communicate messages to other nerves or produce specific actions on body organs. Nicotine activates only certain of the receptors that bind acetylcholine. These receptors are now called nicotinic cholinergic receptors. Using the selective action of nicotine on cholinergic receptors, scientists are able to observe their activity separately from muscarinic cholinergic receptors, receptors activated by a chemical called muscarine. Nicotinic cholinergic receptors are located at the ganglia in the autonomic nervous system, where there are specialized areas for communications between nerves, in the adrenal gland, at the neuromuscular junctions, where nerves attach to and activate muscles, and in many parts of the brain.
The greatest number of nicotine cholinergic receptors in the BRAIN are found in the hypothalamus, hippocampus, thalamus, midbrain, brain stem, and many parts of the cerebral cortex. Nicotine acts on sensory receptors, including those that mediate pain sensations. The effects of nicotine on these specific receptors have been an important tool in studying the effects of neurotransmitters on cell receptors and on the nervous system as a whole. In addition, these studies provide information about the widespread effects of nicotine introduced into the body during tobacco use.
DEVELOPMENT OF PHYSICAL DEPENDENCE ON NICOTINE
Nicotine is the chemical substance responsible for PHYSICAL DEPENDENCE on tobacco products. During the development of physical dependence on a drug such as nicotine, brain chemistry and function change. They return to normal in the presence of nicotine and come to depend on the drug for normal function.
The change that results in normal function in the presence of nicotine is called neuroadaptation or TOLERANCE. When tolerance develops after a period of use of nicotine, or of any drug, the same dose produces less of an effect than previously. Tolerance develops to many of the effects of nicotine. It is well-known that people smoking their first cigarette often experience nausea and vomiting. However, after repeated exposure to cigarette smoke, these effects disappear. Their disappearance is the development of tolerance to the toxic effects of nicotine in the cigarette smoke. Tolerance also develops to the more desirable effects of nicotine such as pleasure and alertness.
The development of tolerance is associated with changes in the brain, such as an increased number of nicotinic cholinergic receptors found in the brains of smokers studied at autopsy. The changes in the brain correspond to a state in which the tolerant brain comes to depend on nicotine for normal functioning. This state is called physical dependence.
Physical dependence also means that abstinence or WITHDRAWAL symptoms occur when a person who has taken a drug on a regular basis stops taking it. Physical dependence on nicotine has been clearly demonstrated. Thus a person who stops using tobacco after his or her body has adapted to the presence of nicotine will experience withdrawal symptoms in the form of irritability, restlessness, drowsiness, difficulty concentrating, impaired job performance, anxiety, hunger, weight gain, sleep disturbances, slow down in heart rate, and a strong urge for nicotine. In general, withdrawal symptoms are opposite to the effects produced by nicotine when a person who is not tolerant uses it. Thus a person will start using tobacco primarily to experience the desired effects of nicotine, but once the ADDICTION develops, use of tobacco may be chiefly to prevent the emergence of unpleasant withdrawal symptoms. Use of a drug to prevent withdrawal is common in people who are addicted to a drug.
ABSORPTION OF NICOTINE FROM TOBACCO
Nicotine, which is absorbed into the body when tobacco products are used, can be absorbed by different routes and at different rates. Some products deliver nicotine in smoke that is inhaled. In tobacco smoke, nicotine is present in droplets that also contain water and tar. These droplets are carried by gases that include carbon monoxide, hydrogen cyanide, and nitrogen oxides. Such suspended droplets carried by gas are called an aerosol. When the aerosol is inhaled, the droplets are deposited in the small airways of the lungs, from which nicotine is absorbed into the blood stream. After absorption through the lungs, blood containing nicotine moves into the heart and then into the arterial circulation, including the brain. Nicotine reaches the brain within 10 to 15 seconds after a puff on a cigarette. This rapid delivery of nicotine to the brain produces more intensive effects than following slower delivery and provides the close temporal link between SMOKING and the development of addiction.
Nicotine is absorbed into the body in other ways. It can be absorbed in the mouth even if not inhaled in pipe or cigar smoke. In addition, not all tobacco products deliver nicotine through smoke. Chewing tobacco consists of shredded tobacco or plugs of tobacco that are enhanced with licorice and other flavorings. These products are periodically chewed, and the saliva generated is spat out, hence the term spit tobacco. Oral snuff is finely cut tobacco. A portion of oral snuff, called a pinch, is placed between the lip and the gum. Nicotine is absorbed from these forms of tobacco more slowly than from inhaled smoke, but the total amount absorbed is similar. Nasal snuff is finely powdered tobacco that is sniffed into the nose, where nicotine is rapidly absorbed.
DOSES OF NICOTINE TAKEN IN TOBACCO
The dose of nicotine absorbed from a cigarette is on average about 1 milligram (mg). The average user smokes about 25 cigarettes a day, an average nicotine intake of 20 to 30 mg daily. The average amount of nicotine absorbed from chewing tobacco or snuff per day is similar to that obtained from cigarettes. A person who smokes 25 cigarettes a day will absorb about 200 grams of nicotine in 20 years of smoking.
Nicotine is available as a medication, used to assist people in quitting smoking (see articles on NICOTINE DELIVERY SYSTEMS and TREATMENT of smoking and TOBACCO abuse). These medications are meant to provide nicotine to smokers as a substitute for nicotine formerly consumed from tobacco use. Nicotine medications reduce withdrawal symptoms and increase the likelihood that the individual will quit tobacco use. Two forms of nicotine medication are currently available. Nicotine chewing gum (nicotine polacrilex, also known as Nicorette) consists of nicotine in a gum that slowly releases nicotine during chewing. Each gum is typically chewed for about 30 minutes. People chew up to 16 pieces per day when trying to quit smoking.
Nicotine patches are applied to the skin. They release nicotine slowly through the skin over 16 or 24 hours, depending on the patch used.
Both forms of nicotine-replacement medication deliver doses of nicotine equivalent to that taken in by the average tobacco user. Nicotine chewing gum delivers about 1 to 2 mg per piece. Nicotine patches deliver from 5 to 21 mg, depending on the patch and its strength.
ELIMINATION OF NICOTINE FROM THE BODY
Nicotine in the body is eliminated primarily by breakdown by the liver. The rate of breakdown is such that the level of nicotine in the blood falls about one-half after two hours. This rate is also known as a half-life of two hours. The primary breakdown product of nicotine is cotinine. Cotinine levels in the body are about 10 times higher than those of nicotine. The half-life of cotinine is 16 hours, and cotinine persists in the body for 4 days after a person stops smoking. Cotinine levels can be measured as an indicator of how much nicotine a person is taking in.
Addiction to nicotine is well documented. The development and characteristics of nicotine addiction are described in detail in a report from the U.S. Surgeon General published in 1988. In this report, The Health Consequences of Smoking: Nicotine Addiction, the surgeon general presents criteria for nicotine addiction including the following:
- Highly controlled or compulsive use. Smokers have great difficulty abstaining. Seventy percent of the 45 million smokers in the United States today report that they would like to quit and can not.
- Psychoactive effects. Nicotine, as described earlier in this article, has pronounced effects on the brain.
- Drug-reinforced behavior. Tobacco use is motivated by a desire for the effects of nicotine. People do not smoke cigarettes that do not contain nicotine. Very few people choose to smoke cigarettes that deliver very low doses of nicotine. (See also the article on tobacco.)
Other factors lead to the conclusion that nicotine is addictive:
- It is used despite harmful effects. Most people know that smoking is harmful to their health and continue to smoke. Many people who have nicotine-related diseases are still unable to quit.
- RELAPSE following abstinence. Most smokers can quit for a few days or even weeks (abstinence), but most of these smokers return to smoking within a month. Typically, it takes four or five attempts before a smoker is successful at quitting permanently.
- Recurrent drug cravings. Most smokers have an intense craving or urge to smoke when they have not smoked for some period of time.
- Physical dependence
- Pleasurable effects
The last three factors were described previously.
Smokers carefully regulate nicotine intake to maintain desired levels of nicotine in the body. Such careful regulation is further evidence that nicotine is addictive. Smokers keep the amount of nicotine obtained from cigarettes constant in two ways.
- When people are given cigarettes that are labeled as low-yield (see tobacco history for detailed discussions of yields), they smoke more intensively to obtain the same dose of nicotine they were used to obtaining from the higher-yield cigarettes.
- When they are forced to cut down on the number of cigarettes they smoke each day, they will take in more nicotine per cigarette. Thus when smoking is restricted, smokers tend to maintain the nicotine in their bodies at close to levels maintained during unrestricted nicotine intake.
BEHAVIORAL ASPECTS OF TOBACCO ADDICTION
People continue to smoke both because they enjoy the direct drug effects of nicotine and because use of nicotine becomes associated with other pleasures through learningor instance, when the pleasurable effects of nicotine occur repeatedly in the presence of specific cues or events in the environment. Eventually, those cues and events become a signal to smoke. For example, people often smoke after meals, while drinking a cup of coffee or an alcoholic beverage, during a break from work, while talking on the phone, or while with friends who smoke. After smoking in these situations hundreds of times, the user may find that these situations themselves produce a powerful urge for a cigarette.
There are other learned pleasures that keep people smoking independent of the pharmacological effects of nicotine. Handling of smoking materials, and the taste, smell, or feel of tobacco smoke in the throat, all can become associated with the effects of nicotine and then become pleasurable in themselves. A person who tries to quit must learn to give up not only the pharmacological actions of nicotine but also the aspects of smoking that have become pleasurable through learning. Urges aroused after learning an association between aspects of the environment and the pleasures of smoking prompt relapses in many people who have already overcome withdrawal from nicotine and quit tobacco use.
Smokers report many other reasons for their habit. For example, many smokers, particularly women, smoke to maintain lower body weight. Others seem to use tobacco to control mood disturbances, such as DEPRESSION or ANXIETY.
COMPARISON OF ADDICTION TO NICOTINE AND OTHER DRUGS
Nicotine addiction is similar to and as powerful as addiction to other drugs, such as HEROIN, ALCOHOL, and COCAINE. All these drugs have psychoactivity and produce pleasure. They increase the likelihood that people will spend time looking for them and engaging in rituals while taking them and that users will continue to take them in the face of risk to their well-being and health. The psychoactivity of nicotine is subtle and does not interfere with normal functioning in daily life. Thus nicotine's psychoactivity differs from that of heroin and cocaine, which produces more intense euphoria and may be disruptive to everyday functioning. Despite this difference, nicotine is addictive. A subtle psychoactive effect, especially when experienced with each puff of smoke, taken hundreds of times a day, exerts a powerful effect on behavior over time. The magnitude of effect becomes apparent when each puff of cigarette is considered as a dose of nicotine. A smoker who takes 8 puffs per cigarette and smokes 20 cigarettes per day is receiving up to 160 doses of nicotine per day. The dosing is equivalent to 58,400 doses a year, or 1,168,000 doses after 20 years of smoking.
When difficulty in quitting and relapse after attempting to quit are compared, it becomes apparent that nicotine is even more addictive than other drugs of abuse. Ninety percent of all people who smoke cigarettes are addicted and have difficulty quitting. In contrast, only about 10 percent of people who drink alcohol at all have difficulty controlling use and would be classified as addicted. The percentage of occasional versus addicted users of heroin and cocaine is not known, but when multidrug users are asked about which drug they would have most difficulty giving up, the choice is most commonly nicotine (that is, cigarettes). Relapse rates among adults after cessation of alcohol, heroin, and tobacco use are similar.
NICOTINE ADDICTION IN YOUTH
Ninety percent of all tobacco users begin smoking before the age of 20. The earlier in life one starts smoking, the more likely he or she is to become a regular smoker and the more cigarettes he or she will smoke as an adult. The development of addiction in youth involves a series of steps including
- a trying stage
- regular smoking
- nicotine addiction
The typical interval between trying and addiction is 2 to 3 years.
Initially, young people smoke for social and psychological reasons. The motivations include the influence of parents and friends who are smokers, and the positive images of smoking perpetuated in television and movies and in advertisements in magazines, at music and sports events, and on billboards. Personal factors also play a role. Some include poor school performance, low self-esteem, poor self-image, sensation seeking, rebelliousness, failure to take seriously the adverse effects of tobacco use, and depression or anxiety. While early stages of smoking usually consist of occasional sessions with friends, tolerance develops and withdrawal symptoms are experienced between cigarettes as smoking becomes more frequent. Many youths report withdrawal symptoms and difficulty quitting. They consider themselves addicted to tobacco.
TREATMENT OF NICOTINE ADDICTION
Treatment of nicotine addiction is discussed in the articles entitled Treatment: Tobacco. The approach may be summarized as follows. Initial therapy usually does not include drugs. Smokers are encouraged to pick a day and just stop (go cold turkey). Some smokers participate in formal behavioral therapies, such as those available in smoking-cessation clinics. Those who are unable to stop on their own or with behavior therapies are more likely to be highly addicted to nicotine and are candidates for pharmacological (drug) therapy. The main drug therapies for smoking are nicotine-containing medications such as chewing gum or transdermal (skin) patches.
(SEE ALSO: Addiction: Concepts and Definitions; ; Reward Pathways and Drugs; Tobacco: Smokeless; Tolerance and Physical Dependence; )
BENOWITZ, N. L. (1988). Pharmacologic aspects of cigarette smoking and nicotine addiction. New England Journal of Medicine, 319, 1318-1330.
U.S. SURGEON GENERAL. (1988). The health consequences of smoking: Nicotine addiction. Washington, DC: U.S. Government Printing Office.
NEAL L. BENOWITZ
ALICE B. FREDERICKS