Nicotine 319kinson’s or Alzheimer’s disease. Even though “association” does not demon-
strate cause and effect, some experiments using pharmaceutical nicotine to
treat those afflictions show positive results. Such results, however, have not
yet given nicotine a generally accepted role in treating those diseases. Nicotine
reduces hunger pains and raises blood sugar, effects that help users eat less
(Native Americans have traditionally chewed tobacco to better endure circum-
stances involving little food, water, or rest). Nicotine initially raises blood
pressure, but continued dosage will lower it.
Drawbacks.Tobacco smoking can lead to lung cancer and heart disease.
Many other afflictions are attributed to tobacco smoking: bronchitis, emphy-
sema, cataracts, mouth cancer, pancreas cancer, bone density loss (making
broken bones more likely), abdominal aortic aneurysm (a sac ballooning out
from the blood vessel wall), brain aneurysm, and gastroesophageal reflux (re-
current backward flow of acid and partially digested food from the stomach
to the esophagus, making esophageal cancer more likely). One study noted
that smoking tends to produce changes causing women to go through men-
opause at a younger age than nonsmokers. Laboratory tests imply that smoke-
less tobacco promotes tooth decay. Still more unwanted actions are known,
partly because tobacco has simply been studied so intensively that more is
known about it than is known about many other substances. Whether nicotine
itself causes afflictions produced by tobacco is uncertain. For example, some
investigators suspect that heart disease in smokers comes from carbon mon-
oxide and tar constituents of smoke rather than the nicotine.
In adults 40 mg to 100 mg of pharmaceutical nicotine can produce fatal
poisoning; an equivalent dose through cigarettes would require a person to
quickly smoke several packs. Smaller dosages can be dangerous for children
who play with nicotine patches or gum or who consume tobacco.
Abuse factors.As with many drugs, persons often find nicotine unpleasant
at first but learn to ignore bad sensations and focus upon effects that are
enjoyed. Experiments examining differences that users perceive in various
drugs find that some sensations from nicotine, amphetamine, and cocaine are
similar, so similar that in one experiment persons receiving injections of nic-
otine typically identified it as cocaine. A user can establish a physical de-
pendence with nicotine, causing withdrawal symptoms if dosage stops:
nervousness, tenseness, crankiness, lightheadedness, broken sleep, weariness,
distractedness, tremors. These symptoms often last a few days, sometimes
longer, and can relate to a person’s expectations (a psychosomatic component).
Debate exists about how addictive nicotine is. A study published in 1994
noted that about 33% of tobacco smokers become addicted. A study published
in 2000 found that 20% to 60% of adolescent smokers are addicted. Many
smokers with no interest in quitting can nonetheless substantially reduce their
cigarette consumption with little difficulty. In contrast, many smokers wanting
to stop find themselves unable to cease, and for them even pharmaceutical
nicotine can be an insufficient replacement for tobacco. Among such persons
the persistence of a smoking habit suggests that something more than the drug
nicotine is involved. Tobacco smoke contains thousands of chemical ingredi-
ents besides nicotine; perhaps some of the less-studied ones are important. In
addition, the paraphernalia and mechanics of cigarette smoking provide a