TABACCO
Solanaceous plant to which C. Linnaeus gave the name *Nicotiana tabacum* in honour of J. Nicot of Villemein, who first cultivated the plant in the Portuguese royal gardens. There exist numerous species and varieties (according to some authors up to 60 species), almost all of American origin. The first shipment of seeds from Brazil to France dates to 1556, through the efforts of the monk André Thevet.
The habit of smoking tobacco began in Europe, first in Spain (1570), then in England (1586), and in its early years was especially adopted in France to relieve toothache. In the time of Louis XIII smoking became a habitual indulgence, though initially it was forbidden in the streets and public places, so much so that special premises (*tabagies*) existed for smokers. While the habit of smoking spread increasingly among the less affluent classes, among the aristocracy the use of snuff was already prevalent in the 17th century. Charles I of England was the first to exploit the habit of smoking economically by establishing a state monopoly.
Tobacco, which entered Europe as a medicinal plant, has now practically lost all therapeutic use; only in Greece, Spain, Portugal and Romania are its leaves still official and regularly listed in their respective pharmacopoeias. In the botanical field, the insecticidal action of nicotine is exploited by using tobacco infusion in the fight against aphids.
In relation to the presence in tobacco leaves of a percentage of nicotine (an alkaloid very toxic to the organism) ranging from 0.6 to 7 or 9%, excessive smoking can produce poisoning phenomena. Today, however, it is believed that these are due only in part to nicotine, while other factors come into play, in addition to individual predisposing factors, including the release of other substances during the combustion of tobacco (pyridine bases, ammonia, phenolic and pyrrolic bodies, hydrocyanic acid, carbon monoxide, formaldehyde, etc.).
Acute poisoning is now rare, owing to the great ease with which the organism becomes accustomed to nicotine. It suffices to consider that this would be lethal at a dose of 5–10 centigrams, that in a cigarette (equivalent to about one gram of tobacco) there are on average 2 centigrams of nicotine, and that by inhaling the smoke about 90% of the alkaloid is absorbed. The mechanism of such habituation is not yet clear and seems comparable to that which occurs with arsenic. Acute poisoning, often fatal, was more frequent in the past, when tobacco enemas were used against constipation or tobacco leaf poultices for eye diseases.
Chronic poisoning, also called “tabagism,” is more frequent and is thought to be largely caused by a particular individual predisposition. The symptoms are mainly: cardiovascular (palpitations, arrhythmias, anginal syndromes, intermittent claudication), gastric (of a dyspeptic type or even of gastric hyperacidity and gastritis), visual (scotomas, photophobia, amaurosis, disturbances of colour sense), nervous (insomnia, migraine, tremors, vertigo, vascular spasms), in addition to symptoms of local irritation of the upper airways and oral mucosa (by some authors cancer of the tongue, lip and lung is related to the action of smoking). Even the tobacco industry can give rise to skin diseases of an eczematiform type, which are considered occupational diseases; abortion is frequent among women workers in the tobacco industry.
Tabagism develops with considerable slowness, and its severity does not depend so much on the quantity of tobacco used as, as has already been said, on individual factors not yet known. Many authors agree in stating that moderate use of tobacco is not to be considered harmful in a healthy adult, whereas it can be the cause of serious disorders if there are existing damage to the heart, vessels or nervous system. The treatment of tabagism is based solely on the cessation of tobacco use, and, if there are no permanent organic lesions, the disappearance of all functional symptoms occurs slowly by this means alone. The withdrawal phenomena are not at all comparable to those of morphine, but are purely psychic in nature and easily overcome with a little willpower.