Drug Types 19that the more a person uses, the stronger the drug’s hold. Researchers have
found this assumption to be incorrect for nicotine. Measured by strength of
dependence symptoms, a person who smokes more than a half pack of tobacco
cigarettes each day may be no more addicted than a person who smokes just
half a pack,^18 meaning the lighter smoker may have just as much trouble
quitting as the heavier smoker.
Among cigarette users, the amount of smoking depends in part on the to-
bacco’s nicotine content, but other factors are also involved. During the 1990s
in the United States female smokers tended to have a higher degree of tobacco
addiction than male smokers did (measured not in number of cigarettes
smoked but in strength of addiction symptoms such as tolerance, withdrawal,
and difficulty in reducing consumption).^19 Whites had stronger levels of ad-
diction than did members of other races.^20 Adolescents tended to smoke fewer
cigarettes than middle-aged persons, but despite adolescents’ lower usage,
their addiction symptoms were just as strong as those found in heavier-
smoking middle-aged persons.^21 Older smokers were the least addicted even
though they were the heaviest users.^22 Researchers are unsure whether such
differences are caused by biology or culture or a combination.
In the United States tobacco smoking is associated with being an adult, and
adolescents may take up the practice partly as a symbol of their passage into
adulthood. Role models are also important; a prominent person who smokes
may inspire admirers to do so. Celebrity endorsements of cigarettes were once
routine in advertising, but the admired person can also be a personal acquain-
tance. A survey in Spain revealed that the role model of teachers who smoke
seems to be a major factor in starting the habit among students there.^23
The popularity of smoking among American teenagers declined in the 1970s
and 1980s but increased in the 1990s. A cancer statistics authority reported
that by 1997 over 33% of American high schoolers were using cigarettes.^24 A
study of Taiwanese high school students published in 1999 found a much
lower usage rate, more like 10%.^25 In 1999 a survey of over 14,000 young adult
American college students found about 33% using some sort of tobacco prod-
uct, mostly cigarettes.^26 The latest statistics can be found through the “Sources
for More Information” at the end of this book.
For information about specific pyridine alkaloids class stimulants, see al-
phabetical listings for:areca nutandnicotine.
DEPRESSANTS
Depressants generally have the opposite effect of stimulants. Many depres-
sants are used as sedatives or tranquilizers, terms often used as if they mean
the same thing even though some experts would dispute such interchangeable
usage of the terms sedative and tranquilizer. Depressant drugs slow a person
down, and one result can be reduction of tension, which in turn can improve
a mentally depressed mood. Depressant withdrawal symptoms typically in-
clude uneasiness and sleeping difficulty. If dependence is strong enough,
withdrawal may also involve tremors, loss of strength, delirium, and seizures.
Gradual reduction in dosage may help avoid withdrawal symptoms, but much
depends on the particular drug and the strength of dependence.