Nature's Pharmacopeia: A World of Medicinal Plants

Chapter 13

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Tobacco

Nicotiana tabacum

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Tobacco leaves and flowers adorn the capital of a column in the U.S. Capitol, Washington, D.C. (Photograph by Winnie Lee)

Wild and cultivated tobaccos are leafy annual plants generally not reaching a height of more than 1 or 2 meters.1 They often produce broad leaves, and their growing stems terminate in tubular yellow, cream, or pink flowers with fused petals and flared petal tips (figure 13.1). Originating in the tropical and subtropical Americas, the genus Nicotiana contains dozens of species historically distributed in the New World, Australia, the South Pacific, and Africa. The center of diversity for domesticated varieties is in the tropical Andes of South America, where the plant has probably been farmed for 5000 to 7000 years.2 Tobacco was dispersed widely by humans in pre-Columbian times: the small-leafed cultivated species (N. rustica) was planted throughout northern South America, Central America, the Caribbean, and southwestern and eastern North America; the large-leafed cultivated species (N. tabacum) was grown in Central America and northern South America. Tobacco relatives of the same genus are used ornamentally, selected for their vibrant flower colors, pleasant bouquet, and tolerance to many pests. Through history, diverse peoples have used the various wild and domesticated Nicotiana species for medicinal, ritual, and social purposes, and they all contain psychoactive chemicals.3 The most widely cultivated variety today is N. tabacum.

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FIGURE 13.1   Tobacco: (top) plants; (bottom) flowers.

EARLY USE IN THE AMERICAS

Tobacco was valued by many nations of the Americas, and its uses were documented by Europeans as they made initial contact with indigenous peoples of the New World. Its role in the traditional practices of native societies has also been described by anthropologists in more recent times. The evidence points to tobacco consumption as diverse in form and nearly universal among the indigenous groups of the Americas (figure 13.2).4 People used tobacco by chewing or sucking on the leaves, drinking tobacco leaf juice or water in which leaves were steeped, licking a tobacco leaf extract, snorting ground tobacco into the nose, taking as a liquid infusion or smoke via enema, applying as a leaf paste onto the body, and by leaf smoke taken into the lungs or blown onto the body, among other variations of consumption.5 In some cases, tobacco was taken on its own; in others, it was combined with various additives. For example, tobacco was on occasion chewed with salt, earth, or lime (alkali) derived from crushed seashells or ashes. Tobacco prepared for chewing, smoking, drinking, and other means of consumption was sometimes mixed with other medicinal plant materials, including hallucinogenic substances.6 Importantly, tobacco consumption among Native Americans cannot easily be described as solely medicinal, recreational, social, ritual, or spiritual because for many peoples these elements were interrelated.

Many indigenous people considered tobacco to have supernatural origins and powers.7 For example, the Winnebago Indians of the southern coast of Lake Michigan held that tobacco was a gift to them from Earthmaker, and they offered it as a tribute to the spirits for blessings. Among other groups, tobacco played important roles in genesis stories. The Yecuana of Venezuela believed that women came from “clay over which tobacco smoke was blown,” and the legends of the Yaqui of Mexico held that an ancient woman had been transformed into tobacco.8 In the diverse cosmologies of the Native Americas, the interdependence of the spiritual and physical worlds is a common feature, and the mediator of contact between these domains was frequently a shaman. In the pursuit of their spiritual responsibilities, shamans took tobacco as a source of supernatural power.

There are numerous accounts of the use of tobacco by spiritual leaders to provide for the well-being of their communities through ritual offerings. For example, the shamans of the Huron Indians of the northern Great Lakes region instructed farmers to burn tobacco in their fields to honor the sky deity and ensure good weather for a bountiful harvest.9 On the Ucayali River of Amazonian Peru, weather shamans “blow tobacco smoke to divert thunderstorms.”10 Along the northwestern California coast, the World Renewal priests of the Yurok and Karok drank tobacco juice and offered tobacco to commemorate the yearly transformation and rebirth associated with the seasons, a ceremony without which they believed the world would cease to exist.11 In addition to its significance in such offerings, tobacco played a role in the curing practices of indigenous shamans.

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FIGURE 13.2   Tobacco in indigenous American medical and social life: (top) an illustration of indigenous tobacco use in sixteenth-century Haiti; a shaman is tending to a patient (lying on the hammock) while other patients are smoking a cigar (standing) or intoxicated by the smoke (lying on the ground); (bottom left) a Mayan man smoking a cigar, depicted on an earthenware vessel, 600–900; (bottom center) a Piegan (Blackfeet) medicine man with a decorated ceremonial pipe; (bottom right) a Sioux man smoking a pipe. ([top]) “Modo che tengono i medici nel medicare gl’infermi” (How doctors heal the sick), woodcut from Girolamo Benzoni, La historia del mondo nuovo [1565]; Library of Congress, Prints and Photographs Division, LC-USZ62-71989; [bottom left] Museo Popol Vuh, Guatemala City; vessel decoration photograph © Justin Kerr, K3386, http://www.mayavase.com; [bottom center] photograph by Edward S. Curtis [1910]; Library of Congress, Prints and Photographs Division, LC-USZ62-117604; [bottom right] photograph by Edward S. Curtis [1907]; Library of Congress, Prints and Photographs Division, LC-USZ62-96972)

Taurepan religious practitioners of Venezuela, for instance, drank tobacco juice to sustain contact with the spirit world and thereby extend their ability to treat illnesses, and shamans of the Caribs gave it to their patients to heal them.12 The shamans of the Mundurucú in the Brazilian Amazon blew tobacco smoke on their patients to remove their illnesses.13 Indeed, the use of tobacco smoke for identifying the source of illness and for curing was common among diverse peoples of the Americas. In numerous accounts from throughout the Americas, shamans are said to have blown tobacco smoke to determine the location of evil materials or spirits within the patient and to prepare the body for treatment. The blown tobacco smoke then served to drive out or appease the maleficent entities. Alternatively, the smoke directed the shaman where to excise the source of illness through a straw.14

Tobacco consumption in the spiritual-medical context was widespread in the Americas, frequently associated with altered states of reality induced by potent tobacco preparations and sometimes enhanced by the addition of other herbs. These effects, and tobacco’s connection to the divine, are consistent with the plant’s role in allowing shamans to communicate with the spirit world on behalf of his or her patients and community. In other instances, tobacco’s perceived spiritual-medical power was harnessed in a variety of forms, by trained healers and common people alike, to treat diverse external and internal conditions. The spiritual and medical uses of tobacco in the traditional Mesoamerican context cannot be dissociated, an inherent duality common in tobacco-related beliefs and practices among numerous indigenous American groups.15

Among the Aztecs, tobacco was applied as a paste to the skin to kill parasites, and it was taken internally by steeping it in boiled water to make an herbal tea. The tobacco leaves were also often chewed or smoked. The Aztec herbal of 1552 lists drinking a beverage of “the intoxicating plant we call piciyetl [N. rustica]” as a treatment “for recurrent disease.”16 Mesoamericans employed tobacco for a variety of illnesses, including eye and ear ailments, toothaches, wounds, rashes, gout, and swelling of the belly.17 In eastern and southeastern North America, the Cherokee used tobacco as an analgesic against cramps and headaches, an anticonvulsant, a diuretic, a treatment for dropsy, a remedy for snakebite, and a medicine for dizziness. The Montauk, Micmac, and Mohegan nations, among others, used tobacco as ear medicine and as a dental anesthetic, the smoke blown toward the sore site or the leaves applied directly.18

Tobacco has also served in the social-bonding customs of indigenous Americans. The people of the Blackfoot nation of Alberta and Montana smoked wild tobacco (N. quadrivalvis) leaves mixed with red osier dogwood (Cornus sericea) at ritual gatherings. In accounts of such rituals, the entire community gathered inside a large tipi, the women and children in a designated section and the men seated in order of wealth and community standing. Men passed the medicine pipe clockwise around the tipi, drew from the pipe precisely four times without inhaling, and blew the smoke upward. At elite, all-night Big Smoke ceremonies, only the wealthiest men of the community participated, and they regaled one another with a prescribed number of songs to vie for prestige among their peers. The Apache, Tewa, and other peoples of the southwestern United States smoked tobacco at medicine ceremonies, and the Paiute smoked it to ward off colds during ritual bathing and prayer.19

Among eastern North American tribes, political or economic agreements were formalized by the ritual exchange of tobacco. In many cases, this took the form of the communal smoking of a pipe, known as a calumet.20 Such ceremonies took place to signify friendship, alliances, and treaties between peoples.21

The diverse cultural uses of tobacco across the Americas gave rise to countless technologies for the ingestion, inhalation, and insufflation of tobacco products. Some indigenous peoples of South America drank tobacco juice or a tobacco infusion out of a hollowed gourd, through either the mouth or the nose.22 Throughout the Americas, people fashioned pipes out of stone, bone, clay, reed, or wood, through which they took smoke into their mouths or lungs.23 Numerous groups rolled dried tobacco leaves in a wrapper made of tobacco, leaves of a different plant, or tree bark. People then lit the ends of these cigars and took the smoke into their mouths or lungs.24 Also common was the use of finely ground tobacco (snuff), sometimes mixed with other materials, taken by tube onto the nasal mucosa.25 Insufflators, as these tubes are known, were often made of bone and took various forms to accommodate one or both nostrils, for self-administration or administration by another. There are also examples of the use of rectally administered tobacco smoke or liquid, introduced by an enema made of materials such as animal bladder, rubber, bone, and reed.26 The apparatus of tobacco consumption served in the ritual, social, and medical use of the herb in various forms. The European explorers who arrived in the New World learned from the indigenous peoples and adopted and adapted their customs.

TOBACCO AS A COLONIAL COMMODITY

When Christopher Columbus (1451–1506) first set foot on the island he called San Salvador (in the Bahamas) on October 15, 1492, the local people offered him tobacco leaves. Two weeks later, while exploring Cuba, his crew members observed “men and women with a firebrand of weeds in their hands to take in the fragrant smoke to which they are accustomed.”27 To Europeans searching for precious metals, exotic spices, and souls to convert to Christianity, the dried leaves held in such high esteem by the Caribbean islanders were at first no more than a curiosity. The earliest Spanish writers described what they saw among the indigenous peoples of the Caribbean and Mesoamerica: people inhaling the smoke of tobacco, chewing tobacco with crushed seashells, and breathing powdered tobacco into their noses through Y-shaped tubes.28 At first a novel New World botanical specimen among many, tobacco did not initially garner much attention by scholars in Madrid, Paris, or elsewhere. As tobacco’s potential medicinal properties captured the Europeans’ interest, however, it was transported by sea and land to the major trading posts of the world. The early explorers brought back to Europe samples of the leaves and seeds, and by the mid-sixteenth century, tobacco was grown in Spanish, Portuguese, Dutch, and French botanic gardens. By the end of the sixteenth century, tobacco was known throughout Europe and had been taken to Russia, Japan, China, India, and parts of Africa.29 In less than 100 years, tobacco was propagated around the globe.

First the Spanish and later the Portuguese, English, Dutch, and French colonists cultivated tobacco both because they recognized its utility in trade with the indigenous Americans and because they themselves became accustomed to its physiological effects. In the journal of Columbus’s voyage, tobacco smoke is said to reduce pain and fatigue among the indigenous people of Cuba, “so they say that they do not feel weariness.”30 A French chronicler noted in 1555 that tobacco smoke suppressed hunger and thirst among the natives living along what is now the coast of Brazil.31 Europeans, and the African slaves they brought to the New World, ultimately tried tobacco for many of the same purposes: one account from the 1530s tells of Spaniards smoking tobacco to treat the pain associated with syphilis and describes African slaves smoking to relieve exhaustion.32 Those explorers who smoked found it difficult to give it up, lamenting “that it was not within their hands to stop taking it.”33 Within a few decades of their arrival, a great number of colonists—settlers, sailors, and slaves—were hooked on tobacco.

During the sixteenth century, the Spanish established tobacco plantations in their Caribbean, Central and South American, and Philippine colonies, and the Portuguese grew tobacco in Brazil. The French cultivated tobacco in their short-lived Florida colony. By the turn of the seventeenth century, tobacco was among the first crops grown in the English Jamestown colony.34 The expansion of tobacco growing was driven by increasing demand in Europe and enabled by the plant’s tolerance of relatively diverse climatic and soil conditions.35 Therefore, settlers were able quickly to increase production of a highly adaptable cash crop.

THE PROCESSING OF TOBACCO

The Europeans, no doubt taking cues from inhabitants of the New World, innovated multiple means to consume tobacco.36 Following the harvest of the mature leaves and their slow drying (or curing) in a shaded and airy place, in the sun, or over a slow-burning wood fire, tobacco is processed into a number of products.37 Cigars, as modified by Europeans, contain shredded leaves wrapped into long, thin rods within a large tobacco leaf. Cigars are lit and smoked generally without inhaling deeply, instead allowing the smoke to linger in the mouth. Cigarettes, probably developed in Spanish America during the seventeenth century, contain tobacco leaf fragments rolled in paper, and the smoke is inhaled into the lungs.38 Other types of smoking tobacco, sometimes mixed with fragrant plant oils, are slowly burned in the bowls of pipes or water pipes. Snuff is finely ground, scented tobacco sniffed into the nose, a form considered particularly sophisticated in much of Europe during the seventeenth and eighteenth centuries. Chewing tobacco consists of moist, cured tobacco-leaf pieces that are slowly chewed or held between the lips or cheek and gums.

HEALING HERB OR HEALTH HAZARD?

When Europeans first described tobacco use among American Indians, a common theme in their commentary is the plant’s intoxicating effects. For example, a Spanish account from the mid-sixteenth century explains the consequences of tobacco chewing this way: “He who sells picietl [N. rustica] crushes the leaves first, mixing them with lime, and he rubs the mixture well between his hands. Placed in the mouth it produces dizziness and stupefies.”39 As an inebriant associated with native shamanic rituals, tobacco came to be a concern of some Christian explorers and clergy, who questioned its spiritual wholesomeness. A Dominican cleric in the Caribbean during the first third of the sixteenth century remarked that tobacco snuff “takes away the senses”;40 another visitor to Mexico railed against tobacco in 1541, calling it “a wicked and pestiferous poison from the devil.”41 These admonitions, however, did not prevent colonists from learning to use tobacco.

As colonists and sailors in the New World took up the tobacco habit during the early sixteenth century, botanists and physicians in European centers of learning debated the novel herb’s effects on health.42 In a French agricultural treatise of 1567, the author relays a story of a young boy whose cancerous growth on the nose was completely cured by applying tobacco pulp and a woman whose breast tumor was similarly eliminated, along with tales of treating ulcers, infections, and asthma.43 The elaborate description of New World flora and fauna written by Nicolás Monardes (1493–1588) in 1571 claims that tobacco can be applied externally for skin ailments, muscle stiffness, and stomach pain; drunk as a liquid infusion for chest congestion, internal parasites, and bad breath; and inhaled as smoke to treat asthma, among other uses.44 By 1576, tobacco was lauded as a panacea in a Belgian herbal, “effective for sores, wounds, ailments of the chest and wasting of the lungs.”45 As European scholars grew more familiar with tobacco’s properties, they wrote tracts recommending a degree of moderation in tobacco use and outlined some of its risks. For example, an English guide to tobacco published in 1595 acknowledged the usefulness of tobacco smoke for headaches and arthritis but noted that it should not be taken unless necessary.46 In a book on health published in London in 1600, the author suggests tobacco smoke to treat migraines and toothaches but warned that it was harmful to the brain and liver if taken after a meal.47 By the early seventeenth century, numerous accounts of certain ill effects of tobacco had appeared. Among the most striking is the tract composed by King James I (1566–1625) of England. In A Counterblaste to Tobacco (1604), he famously describes smoking as “a custome lothsome to the eye, hatefull to the nose, harmefull to the braine, dangerous to the lungs, and in the blacke stinking fume thereof, neerest resembling the horrible Stigian smoake of the pit that is bottomelesse.”48

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FIGURE 13.3   Europeans took up smoking tobacco through small pipes: (left) an English smoker; (right) tobacco use in the Netherlands, depicted in David Teniers, Peasants in a Tavern (1633). ([left]) Woodcut from Anthony Chute, Tabaco [1595]; National Library of Medicine, 156492; [right] National Gallery of Art, Washington, D.C., 1991.140.1)

Such concerns notwithstanding, tobacco captured people with particular efficiency; they probably were drawn more to the pleasure it provided than to any specific therapies it performed. Tobacco smoking crossed the Atlantic and attracted countless new habitués in Britain and throughout continental Europe (figure 13.3). As the value of leaves increased, it was the Jamestown settlement in Virginia—established in 1607 in honor of the English king who had written Counterblaste—where tobacco plantations first bolstered the North American economy.49 The plant’s leaves sold in England at luxury-good prices,50 and the growth of Virginia tobacco prompted the importation of the first African slaves to His Majesty’s colonies to tend it.51

In the centuries following its entry into global trade, tobacco played numerous social roles. It retained its traditional value in staving off hunger and thirst among laborers in the New and Old Worlds alike and remained profitable as a material of social bonding, enjoyed in taverns and coffeehouses, royal courts and houses of worship, smoked, snuffed, and chewed. Despite the potential for harm noted by sixteenth- and early-seventeenth-century commentators, European and American physicians conjured dozens of new medical uses for the tobacco plant. Medical uses of tobacco, taken internally or externally, during the seventeenth through nineteenth centuries included treatment for ringworm, earache, constipation, and arthritis; healing of wounds; and prevention of the plague.52

Although the possible risks of tobacco use became better understood in the nineteenth century, and a number of anti-tobacco societies formed to carry on the public debate over tobacco, some physicians and laypeople promoted tobacco’s health benefits well into the twentieth century, sustaining a public denial of the negative consequences of the widespread tobacco habit.53 During times of military conflict, tobacco smoking has long been a reprieve for tired soldiers, and thus during the Crimean War (1853–1856), the Civil War (1861–1865), World War I (1914–1918), World War II (1939–1945), and more recent conflicts, tobacco drew a large cadre of weary souls who grew dependent on the mild euphoria it provided and the sense of sharpened awareness and enhanced reflexes it brought about. The innovation of manufactured cigarettes in Europe and the United States from the 1840s through the 1860s made tobacco especially convenient and cheaper to produce and sell, enhancing its appeal for extensive distribution. Combined with effective branding and marketing schemes, the cigarette came to dominate the tobacco industry, now accounting for more than four-fifths of all leaf harvested.54

Tobacco companies drew from a long list of cultural and medical cues as they constructed effective advertising strategies for their products, an effort that greatly enhanced the spread of tobacco use—whether chewed, smoked, or insufflated—during the nineteenth and twentieth centuries. Importantly, a number of tobacco makers offered products whose health benefits were touted by doctors for improved digestion, as weight-loss aids, for their respiratory advantages, and so forth. This phenomenon of physician endorsement must certainly have convinced legions of Americans that their smoking habits were wholesome (figure 13.4).

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FIGURE 13.4   Advertising tobacco in the United States: (left) manufacturers promoted tobacco through stereotyped images of indigenous Americans, such as in this advertising label for Indian Girl chewing tobacco, 1874; (right) tobacco products were endorsed by physicians through the mid-twentieth century, as in this advertisement for Lucky Strike cigarettes, manufactured by the American Tobacco Company, 1930. ([left] Library of Congress, Prints and Photographs Division, LC-DIG-ds-00874)

Advertisements notwithstanding, physicians noted a rising incidence of lung cancer among smokers during the 1920s and 1930s, and by the 1950s near-conclusive evidence had mounted that tobacco use contributed to cancer and respiratory and heart diseases.55 In July 1957, the U.S. Public Health Service released its first warning that tobacco increases lung cancer risks; the Royal College of Physicians in 1962 and the U.S. Surgeon General in 1964 released reports stating the causal link between smoking and lung cancer, among other deleterious health effects.56 As a result of these findings and numerous others, the U.S. government required labels on cigarette packs to alert smokers of the danger. As evidence has mounted, the labels have become more assertive in tone. In 1966, the mandated message was: “Caution: Cigarette Smoking May Be Hazardous to Your Health.” By 1970, the phrasing became more forceful: “Warning: The Surgeon General Has Determined That Cigarette Smoking Is Dangerous to Your Health.” In 2003, the World Health Organization issued guidelines for the labeling of tobacco products that has resulted in graphic designs and warning labels that occupy, in some cases, an entire side of the packaging. Several newer variations of these labels warn of the multiple negative consequences of tobacco use, including photographs of grotesquely impacted bodies. In nearly fifty countries and jurisdictions, the labels make a more concise statement, translated into many local languages, with one common message: “Smoking Kills.”57

The unhealthful components of tobacco include products of curing and combustion as well as a large number of chemical compounds inherent to Nicotiana or added during the processing, flavoring, and texturing of the tobacco leaf. The chief psychoactive compound in tobacco, nicotine, has some adverse health consequences; however, many of the numerous pulmonary, cardiovascular, and carcinogenic effects can be attributed to other compounds in the product.58 While tobacco has demonstrated negative effects in all its consumer forms, the delivery of tobacco through smoking conveys particular toxicity. Tobacco is thought to result in the premature deaths of 4.3 million people worldwide annually.59

ISOLATION OF TOBACCO’S ACTIVE PRINCIPLE

The chemical in tobacco responsible for its physiological effects is nicotine, an alkaloid first isolated by the German chemists Wilhelm Posselt and Karl Reimann in 1828 and synthesized around the turn of the twentieth century (figure 13.5).60 Nicotine in its pure form is a clear, oily liquid, alkaline in nature. As an aerosol in smoke inhaled into the lungs, ingested, or applied to the skin and mucous membranes, it passes readily into the bloodstream. Although pure nicotine is a base, it can exist in a slightly different structural arrangement in a more acidic (lower pH) environment. In the tobacco plant, nicotine is present in both an acidic form, in which it is joined to other molecules and therefore unavailable for release into a person’s body, and a free-base form that is more prevalent in alkaline conditions. Therefore, traditional American Indian preparations of tobacco using crushed seashells, chalk, or ashes—all alkaline substances—converted nicotine into a more readily absorbed basic chemical form.61

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FIGURE 13.5   Nicotine.

Since nicotine most effectively crosses the mucous membranes under alkaline conditions, tobacco processing can substantially affect the product’s physiological effects. Cigar and pipe tobacco are usually processed to be alkaline, and nicotine in their smoke can enter the body through the mouth. Since cigarette tobacco is usually processed to be slightly acidic, the large surface area of the alveoli in the lungs enhances the otherwise inefficient uptake of nicotine into the body.62 Tobacco blending can modify the acid-base chemistry of cigarette smoke and alter the way nicotine affects smokers. Among the major types of dried leaves, sun-cured leaves are harvested and dried under the sun, air-cured leaves are dried in the shade, and flue-cured leaves are dried in a heated chamber.63 Each process lends a particular aroma profile and chemistry to the smoked product, and many cigarette makers in the United States and Europe mix tobacco in a proprietary blend. In recent decades, the percentage of flue-cured tobacco in cigarette blends has decreased.64 Since flue-cured tobacco is slightly acidic and air- and sun-cured tobaccos are neutral to slightly alkaline, the industry has moved to a type of cigarette that produces a greater dose of free nicotine in its smoke.

PHARMACOLOGICAL EFFECTS OF NICOTINE

Reduction in muscle tone

Increase in attentiveness

Reduction in appetite

Increase in heart rate

Increase in blood pressure

Reduction in urine production

Mild euphoria

Typical tobacco leaves contain between 0.5 and 3 percent nicotine by weight, a figure that varies substantially depending on variety of plant, location on the plant, growing and harvest conditions, and curing technique.65 The tobacco in a single cigarette contains, depending on the manufacture, approximately 10 milligrams of nicotine.66 Less than 10 percent of the nicotine in a cigarette is inhaled and enters the bloodstream via the lungs, mouth, or stomach. The remainder is exhaled without absorption, destroyed by burning, or lost to uninhaled smoke.

MECHANISM OF ACTION

Nicotine exerts its effects by binding as an agonist to nicotinic acetylcholine receptors in the central and peripheral nervous system. In the periphery, nicotine gives rise to increased activity of the gastrointestinal tract and elevated blood pressure and heart rate, in part via the release of epinephrine from the adrenal glands. In the brain, nicotinic receptors are located at the presynaptic terminals of dopaminergic, cholinergic, and glutamatergic neurons. Binding of nicotine causes the release of those neurotransmitters, which accounts for diverse effects on elevating mood and producing euphoria. Nicotine also reduces skeletal muscle tone, contributing to a sense of relaxation. Connections to the opioid and cannabinoid neurotransmitter systems, not yet fully investigated, may underlie some of the pleasure and analgesia resulting from tobacco use. Nicotine decreases appetite and increases psychomotor ability, attention, and memory consolidation. Nicotine is a demonstrated antidepressant, and co-occurrence of nicotine use and depression is an indication that people might self-medicate to reduce depressive symptoms.67

In addition to nicotine, which contributes to cardiovascular disease through an increased workload on the heart and blood vessels, tobacco, especially when smoked, contains numerous processing and combustion byproducts that cause cancer.68 (Nicotine itself is toxic but not carcinogenic.) As awareness of the risks of consuming tobacco has grown in recent years, companies whose fortunes have long depended on the sale of nicotine products have diversified to include the production and marketing of nicotine delivery by other means, including aerosol, lozenge, and “dissolvable tobacco.”69 Indeed, many of the electronic cigarettes (generating doses of vaporized nicotine), nicotine patches, and nicotine chewing gums for smoking cessation are produced by “Big Tobacco.”

When Europeans learned of the tobacco plant from American Indians, they tried to put its combined stimulating and relaxing properties into a medical and social context. Some thought that consumption of the plant was a dignified expression of high class; others found the practice unsavory. Some viewed tobacco as a healthful herb; others saw it as a dangerous poison. In modern times, countries are pulled between the economic value of the tobacco crop and the obligation to protect people from its risks. Such has been the history of this divisive and important psychoactive plant, whose nicotine-laden leaves have gripped so many.