Understanding Drug-taking Behavior1chapter After you hav.docx

Understanding
Drug-taking Behavior
1chapter After you havecompleted this chapter,
you should have an
understanding of
● Basic terminology con-
cerning drugs and drug-
taking behavior
● The ways drugs enter and exit
the body
● Factors determining the
physiological impact of drugs
● The distinction between
physical and psychological
dependence
● The psychiatric definitions of
substance abuse and
substance dependence
● The five-schedule classifica-
tion of controlled substances
in the United States
Mike was seventeen, a high school junior—an age when
life can be both terrific and terrifying. He looked at me with

amazement, telling me by his expression that either the
question I was asking him was ridiculous or the answer was
obvious. “Why do kids do drugs?” I had asked.
“It’s cool,” he said. “That’s why. Believe me, it’s impor-
tant to be cool. Besides, in my life, drugs just make me feel
better. Smoking a little weed, mellowing out with some
Perks or a little Vicodin, spinning with some Addies—it’s a
way of getting away from ‘stuff.’ And you know that every-
body does it. At least all of my friends do it. It’s easy to get
them. All you need to know is where to go.”
The meeting was over. But as he started to leave, Mike
seemed to notice the concern on my face. “Don’t worry
about me,” he said. “I can handle it. I can handle it just
fine.”
P A R T O N E
Drugs and Society:
The Criminal Justice
Perspective

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Drugs, Society and Criminal Justice, 3E by Ken Charles F.
Levinthal.
Published by Prentice Hall. Copyright © 2012 by Pearson
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2 ■ Part One Drugs and Society: The Criminal Justice
Perspective
There is no question that drugs are all around us.
Thousands of Internet web sites offering information

about drug use are just a click away. It seems difficult at
times to pick up a newspaper, watch television, or listen
to popular music without seeing or hearing some refer-
ence to drug use. We are continually bombarded with
news about drug-related arrests of major drug dealers
and ordinary citizens, news about the most recent drug
involvement among popular celebrities, and news about
drugs intercepted and confiscated at our borders and in
the towns and cities of America.
It is also difficult to avoid the reality of drugs in our
personal lives. Seven out of ten adults surveyed in the
United States describe the nation’s drug problem as
either extremely or very serious; one out of four Ameri-
cans report that drugs have been a cause of trouble in
their family. In school, you have been taught the risks
involved in drug use, but it is likely that you have had to
contend with the social pressure to engage in some form
of drug-related activity with your friends. According to a
national survey, about one in five males and about one
in eight females between the ages of twelve and seven-
teen have been approached in the past month by some-
one selling drugs. For fifteen- or sixteen-year-old youths,
the number is approximately one in four. In light of
your own experiences, these official statistics might
appear to be underestimates.1
Two central facts should be kept in mind as we
begin an exploration of present-day issues regarding
drug use and abuse. First of all, the challenges we face
with respect to drug-taking behavior today include not
only the availability of illegal drugs such as cocaine,
amphetamines, heroin, LSD and other hallucinogens,
and marijuana, but also the availability of legally sanc-
tioned drugs such as alcohol and nicotine. The decision

to use drugs of all types and forms, legally sanctioned or
not, has become one of life’s choices in the United
States as well as in nations around the world. Second,
the problems associated with drug-taking behavior
encompass every segment of society; it is not just a
“young people’s issue.” The potential for drug abuse and
drug dependence exists for people of all ages, from the
young to the elderly. The adverse impact on our society
can be seen in the workplace and retirement communi-
ties as well as on street corners, in school yards, and col-
lege campuses. The social and personal problems
associated with drug use extend in one way or another
to men and women of all ethnic and racial groups, geo-
graphic regions, and socioeconomic levels. No group or
individuals should believe themselves exempt.2
Finally, we should recognize the heavy price that
we pay. The direct and indirect monetary costs of drug
abuse in our society are enormous, amounting to hun-
dreds of billions of dollars each year.3 The costs are tra-
ditionally classified in four major areas:
The economic costs of lost workplace productivity
due to absenteeism, industrial accidents, and prema-
ture death of workers.
The health-care expenditures required to treat indi-
viduals with illnesses related to drug use, particularly
with respect to the abuse of tobacco and alcohol.
The costs of drug-related crime borne by the victims
of criminal behavior and the community in which
the criminal activity occurs.
The expense of maintaining a criminal justice system
devoted to the control of illegal drugs.
Most importantly, there are costs that cannot be
calculated in monetary terms. They include the decline

in our collective sense of social order, the diminishment
of personal dignity and self-worth, and the devastating
effect on relationships we have with our families and
individuals around us.
The purpose of this book is to answer your questions
and address your concerns about drugs and behavior in
our society today, particularly as they pertain to criminal
behavior and the criminal justice system in America. In
the chapters that follow, the complex issues of legal and
illegal drugs in the United States will be viewed from a
number of perspectives. As we will see, it is important to
understand the biological, psychological, and sociologi-
cal foundations of drug use. It is also important to under-
stand the history of drug use in order to understand why
drug-taking behavior has been so pervasive a phenome-
non over the many centuries of human history and the
reasons why drug-taking behavior remains so compelling
An accused drug user is led away by an agent in a DEA wind-
breaker on a residential street in Billings, Montana, far away
from the urban communities usually associated with drug use.
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Chapter 1 Understanding Drug-Taking Behavior ■ 3
The pills and capsules shown here represent only a small por-
tion of the thousands of medicinal drugs that are available in
our society today. The potential for abuse and misuse of
many of these legal drugs is significant; the impact of such
drug-taking behavior continues to be a major social problem.
for us in our society today. Finally, we need to under-
stand the ways our society has responded to the problems
of crime and violence associated with drug use. A partic-
ular focus will be on the criminal justice system in the
United States that has been created to reduce the nega-
tive impact of drug-taking behavior.
Social Messages about Drug Use
Unfortunately, we live in a social environment that

sends mixed messages with respect to drug use. The
images of Joe Camel, the Marlboro Man, and the Vir-
ginia Slims Woman in print advertisements for ciga-
rettes are increasingly distant memories, but at one
time they were iconic anchors for marketing cam-
paigns designed to convey the attractiveness of smok-
ing to the public, and particularly to young people.
They are gone now as a result of federal regulations
established in 1998. For decades, warning labels on
cigarette packs and public-service announcements
have cautioned us about the serious health hazards of
tobacco use. Yet cigarette smoking is still often por-
trayed in a positive light in movies and other forms of
entertainment media.
Beer commercials during telecasts of football
games and other athletic events are designed to be fun
and engaging, to associate beer drinking with a desir-
able lifestyle filled with friendship, sex, and romance.
But we are expected to “drink responsibly” or to “know
when to say when.” The social messages about alcohol
drinking inherent in these commercials extend beyond
simply the selling of a product. It has been established
that positive expectancies (such as gaining social accep-
tance) that these commercial engender predict the
onset age of drinking and the transition to high-risk
alcohol use over time.4 Experiences with alcohol abuse
and alcoholism abound, and we fully recognize the
potential for injuries and death as a result of driving
while intoxicated. At the same time, we hear reports
that moderate alcohol drinking (unless contraindicated)
is actually beneficial to our health.
Prominent political figures, including a former
U.S. president (Bill Clinton) and a former U.S. vice-

president (Al Gore), as well as a host of public officials
on local and national levels, have admitted their expe-
riences with marijuana earlier in their lives. Yet the
position of the U.S. government on marijuana is that
it is an illegal substance, officially classified since 1970
as a drug with a high potential for abuse and no
accepted medical use—in the same category as heroin
(see page 24).
Anti-drug campaigns in the media are created to
discourage young people from being involved with
drugs in general. At the same time, we observe a contin-
uing stream of sports figures, entertainers, and other
high-profile individuals engaging in drug-taking behav-
ior. Even though their careers are frequently jeopar-
dized and, in some instances, lives are lost as a result
(see Chapter 2), powerful pro-drug-use messages continue
to influence us. These messages come from the enter-
tainment industry and traditional media sources, as well
as from web sites on the Internet.5
As confusing and often contradictory as these mes-
sages are, they represent the present-day drug scene in
America.
Looking at Drugs and Society
There are two basic ways in which we can look at the
subject of drugs and society. First, we can examine the
biological, psychological and sociological effects of con-
suming certain types of drugs. The focus is on the study
of drugs that alter our feelings, our thoughts, our percep-
tions of the world, and our behavior. These substances
are referred to as psychoactive drugs because they influ-
ence the functioning of the brain and hence our behav-
ior and experience. Examples that often receive the

greatest amount of attention are officially defined in the
psychoactive drugs: Drugs that affect feelings,
thoughts, perceptions, or behavior.
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United States as illicit (illegal) drugs: heroin,
cocaine, and marijuana, along with club drugs
such as methamphetamine (meth), Ecstasy,
LSD, PCP, ketamine, and GHB. Other equally
important psychoactive substances, however, are
licit (legal) drugs, such as alcohol, nicotine, and
caffeine. In the cases of alcohol and nicotine,
legal access carries a minimum-age requirement.
Second, we can focus on the social circum-
stances that lead to drug-taking behavior. We will
examine the possibility that drug use is, at least in
part, a consequence of how we feel about our-
selves in relation to our family, to our friends and
acquaintances, to our life experiences, and to the
community in which we live. An exploration into
the reasons why some individuals engage in drug-
taking behavior, while others do not, will be an
important topic in Chapter 4.
Ultimately, understanding the interplay
between drug-taking behavior and society
(Figure 1.1) is essential when we consider the dan-
gerous potential for drug use to turn into drug
dependence. As many of us know all too well, a
vicious circle can develop in which drug-taking
behavior fosters more drug-taking behavior in a spi-
raling pattern that can be extremely difficult to
break. Individuals showing signs of drug depen-
dence display intense cravings for the drug and, in many
cases, require increasingly greater quantities to get the
same desired effect. They become preoccupied with their
drug-taking behavior and eventually feel that their lives

have gotten out of control.
Current research on drug dependence points to the
need for us to examine the issue on a biological level,
psychological level, and sociological level. On a biologi-
cal level, the use of psychoactive drugs modifies the func-
tioning of the brain, both during the time when the drug
is present in the body and later, when the drug-taking
behavior stops. Drug dependence, therefore, produces
long-lasting brain changes. As one expert has put it, a
“switch” in the brain seems to be thrown following pro-
longed drug use. It starts as a voluntary behavior, but
once that switch is thrown, a pattern of drug dependence
takes over. On a sociological level, drug dependence can
be viewed as the result of a complex interaction between
the individual and his or her environment. We cannot
fully understand the problem of drug dependence with-
out being aware of the social context in which drug-tak-
ing behavior occurs. As we will see in Chapter 16, the
recognition that drug dependence can be defined in
terms of biological and social components has important
implications for designing effective treatment programs.6
Which drugs have the greatest potential for creating
drug dependence? How can someone escape drug
dependence once it is established? What factors increase
or decrease the likelihood of drug-taking behavior in the
first place? What is the relationship between drug-taking
behavior and crime? What impact have social policies
and our system of criminal justice had on drug-taking
behavior? These are some of the important questions we
will consider as we examine the impact of drugs and
drug-taking behavior on our lives.
F I G U R E 1 . 1

Psychoactive Drugs
Physiological Impact on the Brain
Drug-taking Behavior Society
Psychological
Factors
Biopsychosocial Model
Biological
Factors
Sociological
Factors
Understanding the interplay of drug-taking behavior and
society through the biopsychosocial model of drug use.
illicit drugs: Drugs whose manufacture, sale, or pos-
session is illegal.
licit drugs: Drugs whose manufacture, sale, or posses-
sion is legal.
drug dependence: A condition in which an individual
feels a compulsive need to continue taking a drug. In
the process, the drug assumes an increasingly central
role in the individual’s life.
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A Matter of Definition:
What is a Drug?
Considering the ease with which we speak of drugs and
drug use, it seems that it should be relatively easy to
explain what we mean by the word drug. Unfortunately,
there are significant problems in arriving at a clear
definition.

The standard approach is to characterize a drug
as a chemical substance that, when taken into the
body, alters the structure or functioning of the body in
some way. In doing so, we are accounting for exam-
ples such as medications used for the treatment of
physical disorders and mental illnesses, as well as for
alcohol, nicotine, and the typical street drugs. Unfor-
tunately, this broad definition also could refer to ordi-
nary food and water. Because it does not make much
sense for nutrients to be considered drugs, we need to
refine our definition by adding the phrase, excluding
those nutrients considered to be related to normal
functioning.
But we may still be on slippery ground. We can
now effectively eliminate the cheese in your next pizza
from being considered a drug, but what about some
exotic ingredient in the sauce? Sugar is safely excluded,
even though it has significant energizing and therefore
behavioral effects on us, but what about the cayenne
pepper that burns your tongue? Where do we draw the
line between a drug and a nondrug? It is not an easy
question to answer.
We can learn two major lessons from this seemingly
simple task of defining a drug. First, there is probably no
perfect definition that would distinguish drugs from
nondrugs without leaving a number of cases that fall
within some kind of gray area. The best we can do is to
set up a definition, as we have, that handles most of the
substances we are likely to encounter.
The second lesson is more subtle. We often draw
the distinction between drugs and nondrugs not in
terms of their physical characteristics but rather in terms
of whether the substance in question has been intended

to be used primarily as a way of inducing a bodily or psy-
chological change.7 By this reasoning, if the pizza maker
intended to put that spice in the pizza to make it taste
better, the spice would not be considered a drug; it
would simply be another ingredient in the recipe. If the
pizza maker intended the spice to intoxicate you or
quicken your heart rate, then it might be considered a
drug (see Drugs … in Focus).
The problem is that we are trying to reach a con-
sensus on a definition that fits our intuitive sense of
what constitutes a drug. We may find it difficult to
define pornography, but (as has been said) we know it
when we see it. So it may be with drugs. Whether we
realize it or not, when we discuss the topic of drugs,
we are operating within a context of social and cultural
values, a group of shared feelings about what kind of
behavior (that is, what kind of drug-taking behavior)
is right and what kind is wrong. As we will see in
Chapter 3, these values have manifested themselves
over the years in social legislation and a criminal jus-
tice system for the purpose of regulating the use of
specific drugs and specific forms of drug-taking
behavior.
The judgments we make about drug-taking behav-
ior even influence the terminology we use when refer-
ring to that behavior. When we speak of “drug misuse”
and “drug abuse,” for example, we are implying that
something wrong is happening, that a drug is producing
some harm to the physical health or psychological well-
being of the drug user or to society in general.
But what criteria do we use to decide whether a
drug is being misused or abused? We cannot judge on

the basis of whether the drug is legal or illegal, since the
legality of a psychoactive drug may depend more on his-
torical and cultural circumstances than on its chemical
properties. Tobacco, for example, has deeply rooted
associations in American history, dating to the earliest
colonial days. Although it is objectionable to many indi-
viduals and harmful to the health of the smoker and oth-
ers, tobacco is nonetheless legally available to adults.
Alcohol is another substance that is legal, within the
bounds of the law, even though it can be harmful to
individuals who become inebriated and potentially
harmful to others who may be affected by the drinker’s
drunken behavior. The difficulty of using a criterion
based on legality is further complicated by cultural dif-
ferences in communities around the world.
Instrumental and Recreational
Use of Drugs
Given the differences in attitudes toward specific drugs
across cultures and societies, it is useful to look closely
at the relationship between drugs and behavior in terms
of the intent or motivation on the part of the user. Based
upon on the intent of the individual, drug use can be
categorized as either instrumental or recreational.8
drug: A chemical substance that, when taken into the
body, alters the structure or functioning of the body in
some way, excluding those nutrients considered to be
related to normal functioning.
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instrumental use: Referring to the motivation of a
drug user who takes a drug for a specific purpose oth-
er than getting “high.”
Drugs... in Focus
Understanding Drug Names
The names we give to a particular drug can range from a

tongue-twisting generic or chemical term, to a catchy com-
mercial word selected for marketing purposes, to often-
colorful street slang. It is important to keep straight the dif-
ferent circumstances in which a drug name might be used.
We will focus on four major categories of drug names:
brand names, generic names, natural-product names, and
street names.
Brand names
Once a pharmaceutical manufacturer receives official gov-
ernmental approval to hold a patent on a new drug, it has
exclusive rights to sell the drug under a name referred to as
its brand name. The brand name is a registered trademark
of the manufacturer and cannot be used by any other man-
ufacturer for the life of the patent. As examples, while the
drugs are on patent, the stimulant drug Adderall, used in
the treatment of attention-deficit disorder (ADD), is mar-
keted under that brand name exclusively by Teva and Barr
Pharmaceuticals, and the cholesterol-lowering drug Lipitor
is marketed under that brand name exclusively by Pfizer,
Inc. Illicit drugs do not have brand names.
Generic names
The chemical name of a drug is its generic name. Physi-
cians will often write prescriptions for a particular drug
using its generic name (if available), since it is less expen-
sive than its brand name. Once a drug patent has expired,
a drug formerly available under its brand name is now
available under its generic name, sometimes alongside its
brand name equivalent. For example, the nonprescription
analgesic drug Tylenol is marketed by McNeil Consumer
HealthCare in North America and its “sibling” Panadol is
marketed by GlaxoKlineSmith in the United Kingdom and
other countries outside North America under their origi-
nal brand names. Since the patents have long since

expired, they are also marketed as generic drugs under
their generic names, acetaminophen and paracetamol
(para-acetylaminophenol) respectively. Illicit drugs are
referred to by federal and state authorities by their generic
names, unless they are botanical products (see below).
Examples are cocaine hydrochloride, heroin, dextroam-
phetamine, methamphetamine, lysergic diethylamide
(LSD), phencyclidine.
Natural-product names
In some cases, drugs names refer to (1) plants from which
the drugs originate (examples: marijuana, opium, coca,
amanita mushrooms), (2) chemical entities isolated directly
from plants (examples: morphine and codeine from opi-
um poppies, cocaine hydrochloride from the coca plant,
THC from marijuana, psilocybin from psilocybe mush-
rooms, mescaline from peyote cactus), or (3) chemical
entities derived directly or indirectly from plants through a
specific process (example: alcohol created as a result of
the fermentation of grains, free-base cocaine and crack
cocaine created from a chemical modification of cocaine
hydrochloride).
Street names
Street names refer to slang terms generated by a subculture
of drug users for a particular illicit drug or combination of
illicit drugs. Any listing of street names is bound to be
incomplete, as the slang is continually changing. Nonethe-
less, some street names have been around for a long time.
Examples are “speed” for methamphetamine, “smack” for
white heroin, “black tar” for Mexican heroin, “speedball”
for a combination of heroin and cocaine, “grass” or “weed”
for marijuana, and “coke” for cocaine.
By instrumental use, we mean that a person is tak-
ing a drug with a specific socially approved goal in

mind. The user may want to stay awake longer, fall
asleep more quickly, or recover from an illness. If you
are a medical professional on call over a long period of
time, taking a drug with the goal of staying alert is con-
sidered acceptable by most people as long as the drug
does not interfere with one’s duties. Recovering from an
illness and achieving some reduction in pain are goals
that are unquestioned. In these cases, drug-taking
behavior occurs as a means towards an end that has been
defined by our society as legitimate.
The legal status of the drug itself or whether we
agree with the reason for the drug-taking behavior is not
the issue here. The instrumental use of drugs can involve
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prescription and nonprescription (over-the-counter)
drugs that are licitly obtained and taken for a particular
medical purpose. Examples include an antidepressant
prescribed for depression, a cold remedy for a cold, an
anticonvulsant drug to control epileptic seizures, or
insulin to maintain the health of a person with diabetes.
The instrumental use of drugs also can involve drugs that
are illicitly obtained, such as an amphetamine that has
been procured through illegal means to help a person
stay awake and alert after hours without sleep.
In contrast, recreational use means that a person is
taking the drug not as a means to a socially approved goal
but for the purposes of experiencing the effect of the drug
itself. The motivation is to experience a pleasurable feel-
ing or achieve a positive state of mind. Whatever happens
as a consequence of recreational drug-taking behavior is
viewed not as a means to an end but as an end unto itself.
Drinking alcohol and smoking tobacco are two examples
of licit recreational drug-taking behavior. Involvement
with street drugs, in that the goal is to alter one’s mood or
state of consciousness, falls into the category of illicit
recreational drug-taking behavior (Figure 1.2).

Although this four-group classification scheme is
helpful in understanding the complex relationship
between drugs and behavior, there will be instances
in which the category is less than clear. Drinking an
alcoholic beverage, for example, is considered as
recreational drug-taking behavior under most circum-
stances. If it is recommended by a physician for a
specified therapeutic or preventative purpose (see
Chapter 13), however, the drinking might be consid-
ered instrumental in nature. You can see that whether
drug use is judged to be recreational or instrumental
is determined in no small part by the attitudes of the
society in which the behavior takes place. As men-
tioned earlier, these attitudes have a direct influence
on the establishment of drug-regulation laws.
Misuse and Abuse of Drugs
How do the misuse and abuse of drugs fit into this
scheme? Drug misuse typically applies to cases in
which a prescription or over-the-counter (OTC) drug is
used inappropriately. Many instances of drug misuse
involve instrumental goals. For example, drug doses
may be increased beyond the level of the prescription in
the mistaken idea that if a little is good, more is even
better. Or doses may be decreased from the level of the
prescription to make the drug supply last longer. Drugs
may be continued longer than they were intended to be
used; they may be combined with some other drug; or a
recreational use: Referring to the motivation of a drug
user who takes a drug only to get “high” or achieve
some pleasurable effect.
drug misuse: Drug-taking behavior in which a prescrip-

tion or nonprescription drug is used inappropriately.
Taking Valium with a
prescription to relieve
anxiety
Taking No Doz to stay
awake on a long trip
Taking amphetamines
without a prescription to
stay awake the night before
a test
Taking morphine without a
prescription to relieve pain
Having an alcoholic drink
to relax before dinner
Smoking a cigarette or a
cigar for enjoyment
Smoking marijuana to
get high
Taking LSD for the
hallucinogenic effects
Licit Illicit
Instrumental
use
Recreational
use

Legal Status
Goal
F I G U R E 1 . 2
Four categories of drug-taking behavior,
derived from combinations of the user’s
goal and the drug’s legal status.
Source: Expanded from Goode, Erich
(2005). Drugs in American Society (6th ed.).
New York: McGraw-Hill, p. 16.
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prescription drug may (in violation of instructions) be
shared by family members or given to a friend even
though the medical conditions may differ among them.
Drug misuse can be dangerous and potentially
lethal, particularly when alcohol is combined with drugs
that depress the nervous system. Drugs that have this
particular feature include antihistamines, antianxiety
drugs, and sleeping medications. Even when alcohol is
not involved, however, drug combinations can still rep-
resent serious health risks, particularly for the elderly,
who often take a large number of separate medications.
This population is especially vulnerable to the hazards
of drug misuse.
In contrast, drug abuse is typically applied to cas-
es in which a licit or illicit drug is used in ways that
produce some form of physical, mental, or social
impairment. The primary motivation for individuals
involved in drug abuse is recreational. We should
remember that drugs with abuse potential include not
only the common street drugs but also legally available

psychoactive substances such as caffeine and nicotine
(stimulants), alcohol and inhaled solvents (depres-
sants), as well as a number of prescription or OTC
drugs designated for medical purposes but used by some
individuals exclusively on a recreational basis. In
Chapter 7, we will examine recent concerns about the
P O R T R A I T From Oxy to Heroin: The Life and Death of
Erik
Erik lived in a suburban Long
Island, New York community,
and heroin killed him in 2008 at the
age of 19. His mother, Linda D., never
imagined what she was up against. “You
worry,” she has said, “about them smok-
ing pot. You worry about them driving
recklessly. You worry about them not
using their seat belt. You worry about
that phone call in the middle of the
night. You don’t worry about heroin.
Because it didn’t exist in my mindset.”
In the last few years, the reality of
heroin in the suburbs and small towns
of America, previously considered to
be immune from its deadly reach, has
hit home with a sudden and unex-
pected vengeance. As a director of a
local drug-counseling center has
expressed it: “They’re starting
younger, they’re starting with more
substances, they have better access,
everything is cheaper, and they have
more money.” You would call it a per-
fect storm. Heroin arrests have dou-

bled; rehabilitation-facility admissions
of those 21 and under for prescription
pain reliever dependence have tripled
or quadrupled in many cases.
In the case of Erik, it began after
an emergency appendectomy with a
prescription for Vicodin. Erik gradu-
ally entered into a shadowy world of
drug-taking behavior. Finding
new supplies of Vicodin, then
shifting to OxyContin, was easy. “It
sounded grimy and sleazy,” a teenager
would say in reference to her own
dependence on prescription pain
relievers, “but at the time it was just
what I did. Everyone knows someone
who can get them for you.”
At some point in early 2008,
according to Linda, “The oxys dried
up.” Erik turned from pills to heroin.
“It started at a party,” she has said,
“Someone said to him, ‘Oh, try this.’”
By May, Linda and her husband real-
ized Erik was using heroin. In the
weeks that followed, they tried to
convince him to get help. The fami-
ly’s insurance covered Erik’s first trip
to a rehabilitation facility in upstate
New York, but when Erik left after
three days, they told the family that
he had used up their insurance com-
pany’s “once in a lifetime” rehabilita-

tion coverage. They tried to convince
public hospitals to admit Erik, but he
was denied. In the meantime, Erik’s
parents were finding injection nee-
dles around the house and discarded
rubber tubing. They desperately tried
to cobble together funds to pay for
rehabilitation, but they didn’t suc-
ceed in time. Erik died in July.
If Erik had rejected his parents’
efforts to get him help, they would
have faced considerable legal obsta-
cles. In New York State, no one, even
a minor, is required to get treatment
for subst ance abuse. Parents can
petition a county probation depart-
ment to have a drug-abusing child
designated as a Person in Need of
Supervision (PINS), but a court
order has to be issued by a judge for
a PINS child to be admitted for
treatment. Even then, the child may
leave at any time regardless of med-
ical advice to stay.
In the meantime, medical examin-
er statistics indicate that there have
been 173 heroin-related deaths from
2006 to 2009 in a county with a popu-
lation of approximately one million.
One out of ten deaths have involved
an individual under the age of 21,
with the youngest being 14.
Sources: Alterr, Stacey (2009, Novem-

ber 12). Push for heroin help. Newsday,
p. A5. Lefrowitz, Melanie (2009, June
14). Heartbreak of addiction hits home.
Newsday, pp. A4-A6. Archibold,
Randal C. (2009, May 31). In heartland
death, traces of heroin’s spread. New
York Times, pp. 1,24.
drug abuse: Drug-taking behavior resulting in some
form of physical, mental, or social impairment.
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abuse of prescription pain-relievers that contain syn-
thetic opiates or opiate derivatives and are marketed
under such brand names as Vicodin, OxyContin, Per-
cocet, Demerol, and Darvon. In these particular cas-
es, the distinction between drug misuse and drug
abuse is particularly blurry. In the chapters that follow,
when there is no intent to make a value judgment
about the motivation or consequences of a particular
type of drug-taking behavior, we will refer to the
behavior simply as drug use.
Inevitably, decisions over whether a particular form
of drug-taking behavior is categorized as drug use,
abuse, or misuse take into account the potentially harm-
ful physiological effects of the drug in question. It is
important, therefore, to begin with an examination of
the ways in which drugs have an effect on the body.
What is the impact of the manner in which a drug is
administered? What is the impact of timing factors on
the overall effect of a drug? How do we measure its
potential harmfulness? These are some of the questions
we will now address.
How Drugs Enter the Body
Some of you might have heard of the classic public-ser-
vice announcement, which aired frequently on televi-
sion in the late 1980s:

This is your brain (view of egg held in hand).
This is drugs (view of sizzling frying pan).
This is your brain on drugs (view of egg frying in
pan).
Any questions?9
Giving the viewer considerable “food for thought,” its
impact was immediate and unmistakable: Don’t do
drugs because they fry your brain. The creators of this
message were speaking metaphorically, of course. In
effect, they were saying that there are certain classes of
drugs that have a devastating impact on the human
brain. Therefore, stay away from them.
Clearly, psychoactive drugs affect our behavior and
experience through their effects on the functioning of the
brain. Therefore, our knowledge about drugs and their
effects is closely connected with the progress we have
made in our understanding of the ways drugs work in the
brain. A reasonable place to start is to answer the ques-
tion: How do drugs get into the body in the first place?
There are four principal routes through which
drugs can be delivered into the body: oral administra-
tion, injection, inhalation, and absorption through the
skin or membranes. In all four delivery methods, the goal
is for the drug to be absorbed into the bloodstream. In
the case of psychoactive drugs, a drug effect depends
not only on reaching the bloodstream but also on reach-
ing the brain.
Oral Administration
Ingesting a drug by mouth (later digesting it and absorb-
ing it into the bloodstream through the gastrointestinal

tract) is the oldest and easiest way of taking a drug. On
the one hand, oral administration and reliance upon the
digestive process for delivering a drug into the blood-
stream provide a degree of safety. Many naturally grow-
ing poisons taste so vile that we normally spit them out
before swallowing; others will cause us to be nauseated,
causing the drug to be expelled through vomiting.
In the case of hazardous substances that are not
spontaneously rejected, we can benefit from a relatively
long absorption time for orally administered drugs. Most
of the absorption process is accomplished between five
and thirty minutes after ingestion, but absorption may
not be complete for as long as six to eight hours. There-
fore, there is at least a little time after accidental over-
doses or suicide attempts to induce vomiting or pump
the stomach.
On the other hand, the gastrointestinal tract con-
tains a number of natural barriers that may prevent cer-
tain drugs that we want absorbed into the bloodstream
from doing so. One determining factor is the degree of
alkalinity or acidity in the drug, measured by its pH value.
The interior of the stomach is highly acidic, and the fate
of a particular drug depends upon how it reacts with
that environment. Weakly acidic drugs such as aspirin
are absorbed better in the stomach than highly alkaline
Orally consumed drugs are absorbed into the brain relatively
slowly, though for a liquid beverage containing alcohol, the
opposite applies: It is easily absorbed.
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drugs such as morphine, heroin, or cocaine. Insulin is
destroyed by stomach acid, so it cannot be administered
orally, whereas a neutral substance such as alcohol is
readily absorbed at all points in the gastrointestinal tract.
If it survives the stomach, the drug needs to proceed

from the small intestine into the bloodstream. The
membrane separating the intestinal wall from blood
capillaries is made up of two layers of fat molecules,
making it necessary for substances to be lipid-soluble, or
soluble in fats, to pass through. Even after successful
absorption into blood capillaries, however, substances
still must pass through the liver for another “screening”
before being released into the general circulation.
There are enzymes in the liver that destroy a drug by
metabolizing (breaking down) its molecular structure
prior to its excretion from the body. There is a further
barrier separating the bloodstream (circulatory system)
from brain tissue, called the blood-brain barrier, which
determines a drug’s psychoactive effects.
As a result of all these natural barriers, orally
administered drugs must be ingested at deliberately ele-
vated dose levels to allow for the fact that some propor-
tion of the drug will not make it through to the
bloodstream. We can try to compensate for the loss of
the drug during digestion, but even then we may be
only making a good guess. The state of the gastrointesti-
nal tract changes constantly over time, making it more
or less likely that a drug will reach the circulatory sys-
tem. The presence or absence of undigested food and
whether the undigested food interacts with the chemi-
cal nature of the drug are examples of factors that make
it difficult to make exact predictions about the strength
of the drug when it finally enters the bloodstream.
Injection
A solution to the problems of oral administration is to
bypass the digestive process entirely and deliver the drug
more directly into the bloodstream. One option is to
inject the drug through a hypodermic syringe and needle.

The fastest means of injection is an intravenous
(i.v.) injection, since the drug is delivered into a vein
without any intermediary tissue. An intravenous injec-
tion of heroin in the forearm, for example, arrives at
the brain in less than fifteen seconds. The effects of
abused drugs delivered in this way, often called
mainlining, are not only rapid but extremely intense.
In a medical setting, intravenous injections provide an
extreme amount of control over dosage and the oppor-
tunity to administer multiple drugs at the same time.
The principal disadvantage, however, is that the effects
of intravenous administration drugs are irreversible. In
the event of a mistake or unexpected reaction, there is
no turning back unless some other drug is available
that can counteract the first one. In addition, repeated
injections through a particular vein may cause the vein
to collapse or develop a blood clot.
With intramuscular (i.m.) injections, the drug is
delivered into a large muscle (usually in the upper arm,
thigh, or buttock) and is absorbed into the bloodstream
through the capillaries serving the muscle. Intramuscu-
lar injections have slower absorption times than intra-
venous injections, but they can be administered more
rapidly in emergency situations. Our exposure to intra-
muscular injections comes early in our lives when we
receive the standard schedule of inoculations against
diseases such as measles, diphtheria, and typhoid fever.
Tetanus and flu shots are also administered in this way.
A third injection technique is the subcutaneous
(s.c. or sub-Q) delivery, in which a needle is inserted
into the tissue just underneath the skin. Because the
skin has a less abundant blood supply relative to a mus-
cle, a subcutaneous injection has the slowest absorption

time of all the injection techniques. It is best suited for
situations in which it is desirable to have a precise con-
trol over the dosage and a steady absorption into the
bloodstream. The skin, however, may be easily irritated
by this procedure. As a result, only relatively small
amounts of a drug can be injected under the skin com-
pared with the quantity that can be injected into a mus-
cle or vein. When involved in drug abuse, subcutaneous
injections are often referred to as skin-popping.
All injections require a needle to pierce the skin, so
there is an inherent risk of bacterial or viral infection if
the needle is not sterile. The practice of injecting hero-
in or cocaine with shared needles, for example, promotes
the spread of infectious hepatitis and HIV. If adminis-
tered orally, drugs do not have to be any more sterile than
the foods we eat or the water we drink.
Inhalation
Next to ingesting a drug by mouth, the simplest way of
receiving its effects is to inhale it in some form of gaseous
or vaporous state. The alveoli within the lungs can be
imagined as a huge surface area with blood vessels lying
immediately behind it. Our bodies are so dependent
upon the oxygen in the air we breathe that we have
evolved an extremely efficient system for getting oxygen to
intravenous (i.v.): Into a vein.
intramuscular (i.m.): Into a muscle.
subcutaneous (s.c. or sub-Q): Underneath the skin.

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Drugs consumed by inhalation, such as marijuana (shown
here) and tobacco, are absorbed extremely quickly, aided
by a very efficient delivery system from lungs to brain.
its destinations. As a consequence of this highly developed
system, the psychoactive effect of an inhaled drug is even

faster than a drug delivered through intravenous injec-
tion. Traveling from the lungs to the brain takes only five
to eight seconds.
One way of delivering a drug through inhalation is to
burn it and breathe in the smoke-borne particles in the air.
Drugs administered through smoking include nicotine
from cigarettes, opium, tetrahydrocannabinol (THC) from
marijuana, free-base cocaine, crack cocaine, and crystal-
lized forms of methamphetamine. Drugs such as paint
thinners, gasoline, and glues also can be inhaled because
they evaporate easily and the vapors travel freely through
the air. In medical settings, drugs that produce general
anesthesia are administered through inhalation, since the
concentration of the drug can be precisely controlled.
The principal disadvantage of inhaling smoked
drugs, as you probably expect, arises from the long-term
hazards of breathing particles in the air that contain not
only the active drug but also tars and other substances
produced by the burning process. Emphysema, asthma,
and lung cancer can result from smoking in general (see
Chapter 15). There is also the possibility in any form of
drug inhalation that the linings leading from the throat
to the lungs will be severely irritated over time.
Absorption through the Skin
or Membranes
Drug users over the ages have been quite creative in
finding other routes through which drugs can be
administered. One way is to sniff or snort a drug in dust
or powder form into the nose. Once inside the nose, it
adheres to thin mucous membranes and dissolves
through the membranes into the bloodstream. This
technique, referred to as an intranasal administration,

is commonly used in taking snuff tobacco or cocaine.
Prescription medications are becoming increasingly
available in nasal-spray formulations, avoiding the need
for needle injections or difficult-to-swallow pills.
Snuff tobacco, chewing tobacco, and cocaine-con-
taining coca leaves also can be chewed without swallow-
ing over a period of time or simply placed in the inner
surface of the cheek and slowly absorbed through the
membranes of the mouth. Nicotine chewing gums,
available for those individuals who wish to quit tobacco
smoking, work in a similar way. Nitroglycerin tablets for
heart disease patients are typically administered
sublingually, with the drug placed underneath the
tongue and absorbed into the bloodstream.
At the opposite end of the body, medicines can be
placed as a suppository into the rectum, where the sup-
pository gradually melts, and the medicine is absorbed
through thin rectal membranes. This method is less
reliable than an oral administration, but it may be nec-
essary if the individual is vomiting or unconscious.
Another absorption technique involves a transdermal
patch, which allows a drug to slowly diffuse through the
skin. Transdermal patches have been used for long-term
administration of nitroglycerin, estrogen, motion-sickness
medication, and more recently, nicotine. Newly devel-
oped procedures to enhance the process of skin penetra-
tion include the promising technique of administering
low-frequency ultrasound, which allows large molecules
such as insulin to pass through the skin. Insulin adminis-
tration is an especially interesting application because,
until now, the only effective way of getting it into the
bloodstream has been through needle injection.

intranasal: Applied to the mucous membranes of the
nose.
sublingual: Applied under the tongue.
transdermal patch: A device attached to the skin
that slowly delivers the drug through skin absorption.
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Perspective
Drugs… in Focus
Ways to Take Drugs: Routes of
Administration
Oral Administration (by Mouth)
• Method: By swallowing or consuming in eating or
drinking
• Advantages: Slow absorption time; possibility of reject-
ing poisons and overdoses
• Disadvantages: Slow absorption time; no immediate
effect
• Examples: Medications in pill form, marijuana (baked
in food), amphetamine and methamphetamine, barbitu-
rates, LSD (swallowed or licked off paper), PCP, opium,
methadone, codeine, caffeine, alcohol
Injection (by Hypodermic Syringe)
Intravenous Injection
• Method: By needle positioned into a vein
• Advantages: Very fast absorption time; immediate
effects
• Disadvantages: Cannot be undone; risks of allergic
reactions

• Examples: PCP, methamphetamine, heroin,
methadone, morphine
Intramuscular Injection
• Method: By needle positioned into a large muscle
• Advantages: Quicker to administer than an intravenous
injection
• Disadvantages: Somewhat slower absorption time than an
intravenous injection; risk of piercing a vein by accident
• Examples: Vaccine inoculations
Subcutaneous Injection
• Method: By needle positioned underneath the skin
• Advantages: Easiest administration of all injection
techniques
• Disadvantages: Slower absorption time than an intramus-
cular injection; risk of skin irritation and deterioration
• Examples: Heroin and other narcotics
Inhalation (by Breathing)
Smoking
• Method: By burning drug and breathing smoke-borne
particles into the lungs
• Advantages: Extremely fast absorption time
• Disadvantages: Effect limited to time during which
drug is being inhaled; risk of emphysema, asthma, and
lung cancer from inhaling tars and hydrocarbons in the

smoke; lung and throat irritation over chronic use
• Examples: Nicotine (from tobacco), marijuana,
hashish, methamphetamine, ice, free-base cocaine,
crack cocaine, PCP, heroin, and opium
Vaporous Inhalation
• Method: By breathing in vapors from drug
• Advantages: Extremely fast absorption time
• Disadvantages: Effect limited to time during which
drug is being inhaled; lung and throat irritation over
chronic use
• Examples: Surgical and dental anesthetics, paint thin-
ners, gasoline, cleaning fluid
Absorption (through Skin or Membranes)
• Method: By positioning drug against skin, inserting it
against rectal membrane, snorting it against mucous
membranes of the nose, or placing it under the
tongue or against the cheek so it diffuses across blood-
stream
• Advantages: Quick absorption time
• Disadvantages: Irritation of skin or membranes
• Examples: Cocaine, amphetamine, methamphetamine,
nicotine, snuff tobacco, coca leaves
Alternative methods under development include
small silicon chip patches containing a grid of micro-
scopic needles that painlessly pierce the skin and allow
the passage of large molecules into the bloodstream.
Other future techniques may involve the application

of ultrasound waves to increase skin permeability
or the combining of medication with special compounds
that help the medication slip through skin pores.10
Drugs… in Focus summarizes the various ways
drugs can be administered into the body.
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biotransformation: The process of changing the mole-
cular structure of a drug into forms that make it easier
to be excreted from the body.
How Drugs Exit the Body
Having reviewed how a drug is absorbed into the
bloodstream and, in the case of a psychoactive drug,
into the brain, we now will consider the ways in which
the body eliminates it. The most common means of
elimination is through excretion in the urine after a
series of actions in the liver and kidneys. Additionally,
elimination occurs through excretion in exhaled
breath, feces, sweat, saliva, or (in the case of nursing
mothers) breast milk.
The sequence of metabolic (chemical breakdown)
events leading to urinary excretion begins with a process
called biotransformation, chiefly through the action of
specific enzymes in the liver. The end-products of bio-
transformation, referred to as metabolites, are struc-
turally modified forms of the original drug. Generally
speaking, if these metabolites are water-soluble, they are
passed along to the kidneys and eventually excreted in
the urine. If they are less water-soluble, then they are
reabsorbed into the intestines and excreted through
defecation. On rare occasions, a drug may pass through
the liver without any biotransformation at all and be
excreted intact. The hallucinogenic drug Amanita mus-
caria is an example of this kind of drug (see Chapter 9).

A number of factors influence the process of bio-
transformation and urinary excretion and, in turn, the
rate of elimination from the body. For most drugs, bio-
transformation rates will increase as a function of the
drug’s concentration in the bloodstream. In effect, the
larger the quantity of a drug, the faster the body tries to
get rid of it. An exception, however, is alcohol, for which
the rate of biotransformation is constant no matter how
much alcohol has been ingested (see Chapter 13).
The activity of enzymes required for biotransforma-
tion may be increased or decreased by the presence of
other drugs in the body. As a result, the physiological
effect of one drug may interact with the effect of another,
creating a potentially dangerous combination. An indi-
vidual’s age also can be a factor. Because enzyme activi-
ty in the liver decreases after the age of forty, older
people eliminate drugs at a slower pace than do younger
people. We will look at the consequences of drug inter-
actions and individual differences in the next section of
this chapter.
Finally, it is important to point out that drugs are
gradually eliminated from the body at different rates sim-
ply on the basis of their chemical properties. In general,
if a drug is fat-soluble, the rate will be slower than if a
drug is water-soluble. On average, we can look at the rate
of elimination of a particular drug through an index
called its elimination half-life, the amount of time it
takes for the drug in the bloodstream to decline to 50 per-
cent of its original equilibrium level. Many drugs such as
cocaine and nicotine have half-lives of only a few hours;
marijuana and some prescription medications are exam-
ples of drugs with much longer half-lives.11 Understand-
ing the variation in the elimination rates of drugs and

their metabolites is extremely important in the develop-
ment of drug-testing procedures to detect drug-taking
behavior, a topic to be examined in Chapter 12.
Factors Determining the
Behavioral Impact of Drugs
The type of delivery route into the bloodstream, as has
been discussed, places specific constraints upon the
effect a drug may produce. Some drug effects are opti-
mized, for example, by an oral administration, whereas
others require more direct access to the bloodstream.
Other factors must be considered as well. If a drug
is administered repeatedly, the timing of the administra-
tions plays an important role in determining the final
result. If two drugs are administered close together in
time, we also must consider how these drugs might
interact with each other in terms of their acute effects.
Repeated administrations of a drug may produce a
diminished physiological or psychological effect.
Finally, it is possible that two identical drugs taken
by two individuals might have different effects by virtue
of the characteristics of the drug user at the time of
administration.
Timing
All drugs, no matter how they are delivered, share some
common features when we consider their effects over
time. There is initially an interval (the latency period)
during which the concentration of the drug is increasing
elimination half-life: The length of time it takes for a
drug to be reduced to 50 percent of its equilibrium
level in the bloodstream.

metabolite (me-TAB-oh-lite): A by-product resulting
from the biotransformation process.
latency period: An interval of time during which the
blood levels of a drug are not yet sufficient for a drug
effect to be observed.
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0
1
1 2 3 4 5 6 7
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Therapeutic level
Toxic level
Therapeutic
window
F I G U R E 1 . 3

The therapeutic window. Time-release drugs are formulated
to administer the drug in small amounts over time to stay
between the therapeutic level and the toxic level.
in the blood but is not yet high enough for a drug effect
to be detected. How long this latency period will last is
related generally to the absorption time of the drug. As
the concentration of the drug continues to rise, the effect
will become stronger. A stage will be reached eventually
when the effect attains a maximum strength, even
though the concentration in the blood continues to rise.
This point is unfortunately the point at which the drug
may produce undesirable side effects. One solution to
this problem is to administer the drug in a time-release
form. In this approach, a large dose is given initially to
enable the drug effect to be felt; then smaller doses are
programmed to be released at specific intervals afterward
to postpone- up to twelve hours or so- the decline in the
drug’s concentration in the blood. The intention is to
keep the concentration of the drug in the blood within a
“therapeutic window,” high enough for the drug to be
effective while low enough to avoid any toxic effects.
When drugs are administered repeatedly, there is a risk
that the second dose will boost the concentration of the
drug in the blood too high before the effect of the first
dose has a chance to decline (Figure 1.3).
Drug Interactions
Two basic types of interactions may occur when two
drugs are mixed together. In the first type, two drugs in
combination may produce an acute effect that is
greater than the effect of either drug administered sep-
arately. In some cases, the combination effect is purely
additive. For example, if the effect of one drug alone is
equivalent to a 4 and the effect of another drug is a 6,
then the combined additive effect is equivalent to a

value of 10. In other cases, however, the acute combi-
nation effect is hyperadditive, with the combined effect
exceeding the sum of the individual drugs adminis-
tered alone, as in the two drugs in the first example
combining to a value of 13 or more. Any hyperadditive
effect produced by a combination of two or more drugs
is referred to as synergism. In some synergistic combi-
nations, one drug may even double or triple the effect
of another. It is also possible that one drug might have
no effect at all unless it is taken simultaneously with
another. This special form of synergism is called
potentiation; it is as though a drug with no effect at all
by itself, when combined with a drug having an effect
of 6, produces a result equivalent to a 10. The danger
of such interactions is that the combined effect of the
drugs is so powerful as to become toxic. In extreme cases,
the toxicity can be lethal.
In the second type of interaction, two drugs can be
antagonistic if the acute effect of one drug is diminished
to some degree when administered with another, a situ-
ation comparable to a drug with the effect of 6 and a
drug with the effect of 4 combining to produce an effect
of 3. Later chapters discuss drugs that are totally antago-
nistic to each other, in that the second exactly cancels
out, or neutralizes, the effect of the first. Help Line pro-
vides some examples of drug–drug combinations and
food–drug combinations that can present significant
problems.
Tolerance Effects
Legend has it that in the first century B.C., King Mithri-
dates VI of Pontus, a region of modern-day Turkey near
the Black Sea, grew despondent following a series of
military defeats by the Romans and decided to commit
suicide by poison. The problem was that no amount of

poison was sufficient, and the grim task had to be com-
pleted by the sword. It turned out that Mithridates, hav-
ing lived in fear of being poisoned by his rivals, had
taken gradually increasing amounts of poison over the
course of his life to build up a defense or immunity
against this possibility. By the time he wanted to end his
synergism (SIN-er-jih-zum): The property of a drug
interaction in which the combination effect of two
drugs exceeds the effect of either drug administered
alone.
potentiation: The property of a synergistic drug inter-
action in which one drug combined with another drug
produces an enhanced effect when one of the drugs
alone would have had no effect.
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The Possibility of a Drug–Drug or Food–Drug Combination
Effect
It would be impossible to list every known drug–drug
interaction or food–drug interaction. Nonetheless, here
are some examples. Any adverse reaction to a combina-
tion of drugs or a combination of a drug with something
eaten should be reported to your physician immediately.
An awareness of adverse interactions is particularly impor-
tant for elderly patients, who tend to be treated with mul-
tiple medications. The best advice is to ask your physician
whether alcohol, specific foods, or other medications
might either increase or decrease the effect of the medica-
tion that is being prescribed.
Hyperadditive Effects
Alcohol with barbiturate-related sleep medications,
cardiovascular medications, insulin, anti-inflammatory
medications, antihistamines, painkillers, antianxiety
medications
Septra, Bactrim, or related types of antibiotics with

Coumadin (an anticoagulant)
Tagamet (a heartburn and ulcer treatment medica-
tion) with Coumadin
Aspirin, Aleve, Advil, Tylenol, or related painkillers
with Coumadin
Plendil (a blood pressure medication) and Procardia
(an angina treatment), as well as Zocor, Lipitor, and
Mevacor (all cholesterol-lowering medications), with
grapefruit juice
Lanoxin (a medication for heart problems) with
licorice
Lanoxin with bran, oatmeal, or other high-fiber foods
Antagonistic Effects
Morphine/heroin with naloxone or naltrexone
Norpramin or related antidepressants with bran, oat-
meal, or other high-fiber foods
Soy products and certain vitamin K–rich vegetables
such as broccoli, cabbage, and asparagus with
Coumadin
Possible Toxic Reactions
Internal bleeding by a combination of Parnate and
Anafranil (two types of antidepressants)
Elevated body temperature by a combination of
Nardil (an antidepressant) with Demerol (a painkiller)
Excessive blood pressure or stroke by a combination of
Parnate, Nardil, or other monoamine oxidase inhibitors
(MAOIs) used to treat depression with cheddar cheese,
pickled herring, or other foods high in tyramine
Agitation or elevated body temperature by a combina-
tion of Paxil, Prozac, Zoloft, or related antidepressants
with Parnate, Nardil, or other monoamine oxidase
inhibitors (MAOIs) used to treat depression
Irregular heartbeat, cardiac arrest, and sudden death
by a combination of Hismanal or Seldane (two anti-

histamines) with Nizoral (an antifungal drug)
Note: The hyperadditive effects of grapefruit on certain
medications can be dangerous or useful under certain cir-
cumstances. If grapefruit enhances the effect of the cho-
lesterol-reducing medication Lipitor, for example, it is
possible that drinking grapefruit juice might allow the
patient to take less Lipitor (reducing costs and possible
side effects) and still receive the same level of benefit.
Combinations of this kind, however, should be adminis-
tered only under the close supervision of one’s physician.
Where to go for assistance:
www.drugs.com/drug_interactions.php
Check out any combination of prescription or OTC
drugs for potential adverse interactions.
Sources: Graedon, Joe, and Graedon, Teresa (2000, Octo-
ber 16). Say “aaah”: The people’s pharmacy; drugs and
foods can interact adversely. Los Angeles Times, p. 2. Grae-
don, Joe, and Graedon, Teresa (1995). The people’s guide
to deadly interactions. New York: St. Martin’s Press. Sørensen,
Janina M. (2002). Herb–drug, food–drug, nutrient–drug,
and drug–drug interactions: Mechanisms involved and
their medical implications. Journal of Alternative and
Complementary Medicine, 8, 293–308.
life by his own hand, he could tolerate such large doses
that poisoning no longer presented any threat to his life.
This royal case is the first recorded example of drug tol-
erance. In fact, the phenomenon originally was called
mithridatism, and several celebrated poisoners of history,
including the notorious Lucretia Borgia in the early six-
teenth century, were later to use the same defensive
strategy.12

The concept of tolerance refers to the capacity of a
drug dose to have a gradually diminished effect on the
user as the drug is taken repeatedly. Another way of
tolerance: The capacity of a drug to produce a grad-
ually diminished physiological or psychological effect
upon repeated administrations of the drug at the
same dose level.
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viewing tolerance is to say that, over repeated adminis-
trations, a drug dose needs to be increased to maintain
an equivalent effect. A common illustration is the effect
of caffeine in coffee. When you are first introduced to
caffeine, the stimulant effect is usually quite pro-
nounced; you might feel noticeably “wired” after a
5-ounce cup of coffee, containing approximately 100
mg of caffeine. After several days or perhaps a few weeks
of coffee drinking, the effect is greatly diminished; you
may need to be on the second or third cup by that time,
consuming 200 to 300 mg of caffeine, to duplicate the
earlier reaction. Some individuals who drink coffee
regularly have developed such high levels of tolerance to
caffeine that they are able to sleep comfortably even
after several cups of coffee, whereas individuals with
more infrequent ingestions of caffeine end up awake
through the night after a single cup.
Tolerance effects, in general, illustrate the need
for us to look at the interaction between the actual
amount of the drug taken and other factors involved in
the drug-taking behavior. For example, as already noted,
the number of previous times the drug has been used
is crucial; repetition is what tolerance is all about.
Another important factor, however, is the setting with-
in which the drug-taking behavior occurs. There is
strong evidence that tolerance is maximized when the

drug-taking behavior occurs consistently in the same
surroundings or under the same set of circum-
stances.13 We speak of this form of tolerance as
behavioral tolerance.
To have a clear idea of behavioral tolerance, we
first have to understand the processes of Pavlovian
conditioning, upon which behavioral tolerance is
based. Suppose that you consistently heard a bell ring
every time you had a headache. Previously, bells had
never had any negative effect on you. The association
between the ringing bell and the pain of the head-
ache, however, would develop to such an extent that
the mere ringing of a bell alone would now give you a
headache, perhaps less painful than the ones you had
originally but a headache nonetheless; this effect is
Pavlovian conditioning at work.
Pioneering studies by the psychologist Shepard
Siegel showed a similar phenomenon occurring with
drug-taking behavior. In one experiment, one group of
1.1Quick Concept Check
Understanding Drug Interactions
Check your understanding of drug interactions by
assuming the following values to represent the effects of
Drugs A, B, and C, when taken individually:
• Drug A 0
• Drug B 20
• Drug C 35
Identify the type of drug interaction when the following
values represent the effect of two drugs in combination.

1. Drug A combined with Drug B 30
2. Drug B combined with Drug C 55
3. Drug A combined with Drug C 15
6. Drug A combined with Drug B 20
Answers: 1. potentiation 2. additive 3. antagonistic
4. synergistic (hyperadditive) 5. antagonistic 6. additive
Having overdosed on pure heroin, the driver in the car had
already died, and the passenger would die soon afterward.
The police found a needle injected through the driver’s pants
leg. The two men had just cashed their paychecks and
bought the drugs.
behavioral tolerance: The process of drug tolerance
that is linked to drug-taking behavior occurring consis-
tently in the same surroundings or under the same cir-
cumstances. Also known as conditioned tolerance.
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rats was injected with doses of morphine in a particular
room over a series of days and later tested for tolerance
to that dose in the same room. Predictably, they dis-
played a lessened analgesic effect as a sign of morphine
tolerance. A second group was tested in a room other
than the one in which the injections had been given.
No tolerance developed at all. They reacted as if they
had never been given morphine before, even though
they had received the same number of repeated injec-
tions as the first group.
In a more extreme experiment, Siegel tested two
groups of rats that were administered a series of heroin

injections with increasingly higher dosages. Eventual-
ly, both groups were surviving a dosage level that would
have been lethal to rats experiencing the drug for the
first time. The difference in the groups related to the
environment in which these injections were given.
One group received these injections in the colony
room where they lived. When the second group was
receiving the injections, they were in a room that
looked quite different and were hearing 60-decibel
“white noise.” Siegel then administered a single large
dose of heroin, normally a level that should have killed
them all. Instead, rats administered this extremely high
dosage in the same room in which they had received
the earlier heroin injection series showed only a 32 per-
cent mortality rate. When the room was different, the
mortality rate doubled (64 percent). In both groups,
more rats survived than if they had never received
heroin in the first place, but the survival rate was influ-
enced by the environment in which the heroin was
originally administered.
Siegel explained the results of his studies by
assuming that environmental cues in the room where
the initial injections were given elicited some form of
effect opposite to the effect of the drug. In the case of
heroin, these compensatory effects would partially
counteract the analgesic effect of the drug and protect
the animal against dying from potentially high dosage
levels.
The phenomenon of behavioral tolerance, also
referred to as conditioned tolerance because it is based
on the principles of Pavlovian conditioning, explains
why a heroin addict may easily suffer the adverse conse-
quences of an overdose when the drug has been taken
in a different environment from the one more frequently

encountered or in a manner different from his or her
ordinary routine.14 The range of tolerated doses of hero-
in can be enormous; amounts in the 200- to 500-mg
range may be lethal for a first-time heroin user, whereas
amounts as high as 1800 mg may not even be sufficient
to make a long-term heroin user sick.15 You can imagine
how dangerous it would be if the conditioned compen-
satory responses a heroin addict had built up over time
were suddenly absent.
Behavioral tolerance also helps to explain why a
formerly drug-dependent individual is strongly advised
to avoid the surroundings associated with his or her past
drug-taking behavior. If these surroundings provoked a
physiological effect opposite to the effect of the drug
through their association with prior drug-taking behav-
ior, then a return to this environment might create
internal changes that only drugs could reverse. In
effect, environmentally induced withdrawal symptoms
would increase the chances of a relapse. The fact that
1.2Quick Concept Check
Understanding Behavioral
Tolerance through Conditioning
Check your understanding of behavioral tolerance as
proposed by Shepard Siegel by answering the following
questions.
1. Suppose that you have a rat that has been placed in
an environment where it had been repeatedly injected
with morphine. You now inject that rat with a saline
solution (a substance that has no physiological
effect). Assuming that morphine will make a person
less sensitive to pain, how will this animal react to the

saline injection? Will the rat be less sensitive to pain,
more sensitive to pain, or will there be no effect?
Explain your answer.
2. If King Mithridates VI had changed palaces from
time to time during his reign, what would have been
the effect on his eventual level of drug tolerance to
poison when he chose to attempt suicide?
Answers: 1. The rat will now be more sensitive to pain.
The exposure to an environment associated with mor-
phine injections will have induced a conditioned com-
pensatory effect: a heightened sensitivity to pain. The
saline injection produces no physiological effect of its
own; however, because it is given in that same environ-
ment where the morphine was administered, the condi-
tioned effect will remain, and the rat’s reaction will be
hyperalgesia. (The experiment has been performed, by
the way, and this predicted outcome does occur.)
2. Most likely, the king would have died. He would not
have been able to develop a sufficient level of drug toler-
ance to protect himself from succeeding in his suicide
attempt.
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the alcohol in the body) in women makes them feel
more intoxicated than men, even if the same amount
of alcohol is consumed.
Relative to men, women also have reduced levels of
enzymes that break down alcohol in the liver, resulting
in higher alcohol levels in the blood and a higher level
of intoxication.17 We suspect that the lower level of alco-
hol biotransformation may be related to an increased
level of estrogen and progesterone in women. Whether
gender differences exist with regard to drugs other than
alcohol is presently unknown.
Another individual characteristic that influences

the ways certain drugs affect the body is ethnic back-
ground. About 50 percent of all people of Asian descent,
for example, show lower than average levels of one of
the enzymes that normally breaks down alcohol in the
liver shortly before it is excreted. With this particular
deficiency, alcohol metabolites tend to build up in the
blood, producing a faster heart rate, facial flushing, and
nausea.18 As a result, many Asians find drinking to be
quite unpleasant.
Ethnic variability can be seen in terms of other
drug effects as well. It has been found that Caucasians
have a faster rate of biotransformation of antipsychotic
and antianxiety medications than Asians and, as a result,
end up with relatively lower concentrations of drugs in
the blood. One consequence of this difference is in the
area of psychiatric treatment. Asian schizophrenic
patients require significantly lower doses of antipsychotic
medication for their symptoms to improve, and they
experience medication side effects at much lower doses
than do Caucasian patients. Since other possible factors
such as diet, life-style, and environment do not account
for these differences, we can speculate that these differ-
ences have a genetic basis.19
In some cases, differences in the physiological
response to a particular drug can explain differential pat-
terns of drug-taking behavior. For example, researchers
have found recently that African Americans have a
slower rate of nicotine metabolism following the smok-
ing of cigarettes relative to whites. This finding might be
the reason why African Americans, on average, report
smoking fewer cigarettes per day than whites. If we
assume that an equivalent level of nicotine needs to be
maintained in both populations, fewer cigarettes smoked
but a higher level of nicotine absorbed per cigarette will

produce the same effect as a greater number of cigarettes
smoked but a lower nicotine level absorbed per cigarette.
Consequently, African American smokers may be taking
in and retaining relatively more nicotine per cigarette
and, as a result, not having to smoke as many cigarettes
per day.20
conditioning effects have been demonstrated not only
with respect to heroin but with alcohol, cocaine, nico-
tine, and other dependence-producing drugs as well
makes it imperative that the phenomenon of behavioral
tolerance be considered during the course of drug
abuse treatment and rehabilitation.16
Cross-Tolerance
If you were taking a barbiturate (a sedation-producing
drug that acts to depress bodily functioning) for an
extended length of time and you developed a tolerance
for its effect, you also might have developed a tolerance
for another depressant drug even though you have never
taken the second one. In other words, it is possible that
a tolerance effect for one drug might automatically
induce a tolerance for another. This phenomenon,
referred to as cross-tolerance, is commonly observed in
the physiological and psychological effects of alcohol,
barbiturates, and other depressants. As a result of cross-
tolerance, an alcoholic will have already developed a
tolerance for a barbiturate, or a barbiturate abuser will
need a greater amount of an anesthetic when undergo-
ing surgery.
Individual Differences
Some variations in drug effects may be related to an
interaction between the drug itself and specific charac-
teristics of the person taking the drug. One characteris-
tic is an individual’s weight. In general, a heavier person

will require a greater amount of a drug than a lighter
person to receive an equivalent drug effect, all other
things being equal. It is for this reason that drug dosages
are expressed as a ratio of drug amount to body weight.
This ratio is expressed in metric terms, as milligrams per
kilogram (mg/kg).
Another characteristic is gender. Even if a man
and a woman are exactly the same weight, differences
in drug effects still can result on the basis of gender dif-
ferences in body composition and sex hormones.
Women have, on average, a higher proportion of fat,
due to a greater fat-to-muscle ratio, and a lower propor-
tion of water than men. When we look at the effects of
alcohol consumption in terms of gender, we find that
the lower water content (a factor that tends to dilute
cross-tolerance: A phenomenon in which the toler-
ance that results from the chronic use of one drug
induces a tolerance effect with regard to a second
drug that has not been used before.
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Psychological Factors in
Drug-taking Behavior
It is clear that certain physiological factors such as weight,
gender, and race must be taken into account to predict
particular drug effects. Yet, even if we controlled these fac-
tors completely, we would still frequently find a drug
effect in an individual person to be different from time to
time, place to place, and situation to situation. Predictions
about how a person might react would be far from perfect.
A good way of thinking about an individual’s response
to a particular drug is to view a drug effect as essen-
tially a three-way interaction of (1) the drug’s phar-
macological properties (the biochemical nature of the
substance), (2) the individual taking the drug (set),
and (3) the immediate environment within which

drug-taking behavior is occurring (setting).
Whether one or more of these factors dominate in
the final analysis seems to depend upon the dosage level.
Generally speaking, the higher the drug dose, the
greater the contribution made by the pharmacology of
the drug itself; the lower the dose, the greater the contri-
bution of individual characteristics of the drug-taker or
environmental conditions.21
Expectation Effects
One of the most uncontrollable factors in drug-taking
behavior is the set of expectations a person may have
about what the drug will do. If you believe that a drug
will make you drunk or feel sexy, the chances are
increased that it will do so; if you believe that a marijua-
na cigarette will make you high, the chances are
increased that it will. You can consider the impact of neg-
ative expectations in the same way; when the feelings are
strong that a drug will have no effect on you, the chances
are lessened that you will react to it. In the most extreme
case, you might experience a drug effect even when the
substance you ingested was completely inert—that is,
pharmacologically ineffective. Any inert (inactive) sub-
stance is referred to as a placebo (from the Latin, “I will
please”), and the physical reaction to it is referred to as
the placebo effect.
The concept of a placebo goes back to the earliest
days of pharmacology. The bizarre ingredients prescribed
in ancient times to treat various diseases were effective to
the extent that people believed that they were effective,
not from any known therapeutic property of these ingre-
dients. No doubt, the placebo effect was strong enough
for physical symptoms to diminish. During the Middle

Ages, in one of the more extreme cases of the placebo
effect, Pope Boniface VIII reportedly was cured of kidney
pains when his personal physician hung a gold seal bear-
ing the image of a lion around the pope’s thigh.22
It would be a mistake to think of the placebo effect as
involving totally imaginary symptoms or totally imaginary
reactions. Physical symptoms, involving specific bodily
changes, can occur on the basis of placebo effects alone.
How likely is it that a person will react to a placebo? The
probability will vary from drug to drug, but in the case of
morphine, the data are very clear. In 1959, a review of stud-
ies in which morphine or a placebo was administered in
clinical studies of pain concluded that a placebo-induced
reduction in pain occurred 35 percent of the time. Consid-
ering that morphine itself had a positive result in only 75
percent of the cases, the placebo effect is a very strong
one.23
Unfortunately, we cannot predict with certainty
whether a person will react strongly or weakly to a place-
bo. We do know, however, that the enthusiasm or lack
of enthusiasm of the prescribing physician can play a
major role. In one study that varied the attitude of the
physician toward a particular medication, negative
placebo (pla-SEE-bo): Latin term translated “I will
please.” Any inert substance that produces a psycho-
logical or physiological reaction.
The likelihood of a placebo effect is maximized when the
patient highly regards the expertise of the physician prescrib-
ing a drug. This placebo effect will often increase the benefits
of a drug with known therapeutic properties.

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attitudes toward the medication resulted in the least
benefits, whereas positive attitudes resulted in the
most.24

It is not at all clear how the placebo effect is
accomplished. In the case of pain relief, there is evi-
dence that we have the natural ability to increase the
levels of endorphins (internally-produced opiates) in
the bloodstream and the brain from one moment to
the next, but the nature of our ability to alter other
important substances in our bodies is virtually
unknown. Recent studies have documented a 33 per-
cent increase in lung capacity among asthmatic chil-
dren who inhaled a bronchodilator containing a
placebo instead of medication and the development
of skin rashes in people who have been exposed to
fake poison ivy, to name a few examples of placebo-
induced physiological reactions. Placebo research
forces us to acknowledge the potential for psychologi-
cal control over physiological processes in our
bodies.25
Drug Research Methodology
Given the power of the placebo effect in drug-taking
behavior, it is necessary to be very careful when carry-
ing out drug research. For a drug to be deemed truly
effective, it must be shown to be better not only in com-
parison to a no-treatment condition (a difference that
could conceivably be due to a placebo effect) but also
in comparison to an identical-looking drug that lacks
the active ingredients of the drug being evaluated. For
example, if the drug under study is in the shape of a
round red pill, another round red pill without the active
ingredients of the drug (called the active placebo) also
must be administered for comparison purposes.
The procedures of these studies also have to be
carefully executed. Neither the individual administer-
ing the drug or placebo nor the individual receiving

the drug or placebo should know which substance is
which. Such precautions, referred to as double-blind
procedures, represent the minimal standards for separat-
ing the pharmacological effects of a drug from the
effects that arise from one’s expectations and beliefs.26
We will return to the issue of interactions between drug
effects and expectations when we consider alcohol
intoxication in Chapter 13.
Physical and Psychological
Dependence
When we refer to the idea of dependence in drug
abuse, we are dealing with the fact that a person has
a strong compulsion to continue taking a particular
drug. Two possible models or explanations for why
drug dependence occurs can be considered. The first
is referred to as physical dependence, and the second
is referred to as psychological dependence. The two
models are not mutually exclusive; the abuse of some
drugs can be a result of both physical and psycholog-
ical dependence, whereas the abuse of others can be
a result of psychological dependence alone.
Physical Dependence
The concept of physical dependence originates from
observations of heroin abusers, as well as of those who
abuse other opiate drugs, who developed strong physi-
cal symptoms following heroin withdrawal: a runny
nose, chills and fever, inability to sleep, and hypersen-
sitivity to pain. For barbiturate abusers in a compara-
ble situation, symptoms include anxiety, inability to
sleep, and sometimes lethal convulsions. For chronic
alcohol abusers, abstention can produce tremors, nau-
sea, weakness, and tachycardia (a fast heart rate). If

severe, symptoms may include delirium, seizures, and
hallucinations.27
Although the actual symptoms vary with the drug
being withdrawn, the fact that we observe physical
symptoms at all suggests strongly that some kind of phys-
ical need, perhaps as far down as the cellular level,
develops over the course of drug abuse. It is as though
the drug, previously a foreign substance, has become a
normal part of the nervous system, and its removal and
absence become abnormal.
From this point of view, it is predictable that the
withdrawal symptoms would involve symptoms that
are opposite to effects the drug originally had on the
body. For example, heroin can be extremely constipat-
ing, but eventually the body compensates for heroin’s
double-blind: A procedure in drug research in which
neither the individual administering nor the individual
receiving a chemical substance knows whether the
substance is the drug being evaluated or an active
placebo.
physical dependence: A model of drug dependence
based on the idea that the drug abuser continues the
drug-taking behavior to avoid the consequences of
physical withdrawal symptoms.
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intestinal effects. Abrupt abstinence from heroin
leaves the processes that have been counteracting the
constipation with nothing to counteract, so the result
of withdrawal is diarrhea. You may notice a strong
resemblance between the action–counteraction phe-
nomena of withdrawal and the processes Siegel has
hypothesized as the basis for behavioral tolerance.
Psychological Dependence
The most important implication of the model of physi-

cal dependence, as distinct from psychological depen-
dence, is that individuals involved in drug abuse
continue the drug-taking behavior, at least in part, to
avoid the feared consequences of withdrawal. This idea
can form the basis for a general model of drug depen-
dence only if physical withdrawal symptoms appear
consistently for every drug considered as a drug of
abuse. It turns out, however, that a number of abused
drugs (cocaine, hallucinogens, and marijuana, for
example) do not produce physical withdrawal symp-
toms, and the effects of heroin withdrawal are more
variable than we would expect if physical dependence
alone were at work.
It is possible that drug abusers continue to take the
drug not because they want to avoid the symptoms of
withdrawal but because they crave the pleasurable
effects of the drug itself. They may even feel that they
need the drug to function at all. This is the way one
heroin addict has expressed it:
I’m just trying to get high as much as possible…. If
I could get more money, I would spend it all on
drugs. All I want is to get loaded. I just really like
shooting dope. I don’t have any use for sex; I’d rather
shoot dope. I like to shoot dope better than anything
else in the world.28
Many heroin abusers (between 56 and 77 percent
in one major study) who complete the withdrawal
process after abstaining from the drug have a
relapse.29 If physical dependence were the whole story,
these phenomena would not exist. The withdrawal
symptoms would have been gone by that time, and
any physical need that might have been evident
before would no longer be present.

When we speak of psychological dependence,
we are offering an explanation of drug abuse based
not upon the attempt of abusers to avoid unpleasant
withdrawal symptoms but upon their continued
desire to obtain pleasurable effects from the drug.
Unfortunately, we are faced here with a major con-
ceptual problem: The explanation by itself is circular
and tells us basically nothing. If I were to say, for
example, that I was taking cocaine because I was psy-
chologically dependent upon it, then I could just as
easily say that I was psychologically dependent upon
cocaine because I was abusing it. Without some
independent justification, the only explanation for
the concept of psychological dependence would be
the behavior that the concept was supposed to
explain!
Fortunately, there is independent evidence for the
concept of psychological dependence, founded chiefly
upon studies showing that animals are as capable of self-
administering drugs of abuse as humans are. Using tech-
niques developed in the late 1950s, researchers have
been able to insert a catheter into the vein of a freely
moving laboratory animal and arrange the equipment so
that the animal can self-administer a drug intravenously
whenever it presses a lever (Figure 1.4). It had been well
known that animals would engage in specific behaviors
to secure rewards such as food, water, or even electrical
stimulation of certain regions of the brain. These objec-
tives were defined as positive reinforcers because ani-
mals would learn to work to secure them. The question
at the time was whether animals would self-administer
drugs in a similar way. Could drugs be positive rein-
forcers as well?

The experiments showed clearly that animals
would self-administer drugs such as cocaine and oth-
er stimulants despite the fact that these drugs would
not ordinarily produce physical symptoms during
withdrawal. In one study, rats pressed the lever as
many as 6,400 times for one administration of
cocaine; others were nearly as eager for administra-
tions of amphetamines.30 Interestingly, a number of
other drugs were aversive, judging from the reluc-
tance of animals to work for them. Hallucinogens
such as LSD, antipsychotic drugs, and antidepressant
drugs were examples of drugs that animals clearly did
not like.31
By connecting the concept of psychological depen-
dence to general principles of reinforcement, it is possi-
ble for us to appreciate the powerful effects of abused
psychological dependence: A model of drug depen-
dence based on the idea that the drug abuser is moti-
vated by a craving for the pleasurable effects of the
drug.
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drugs. When an animal is presented with a choice of
pressing a lever for food or pressing a lever for cocaine,
cocaine wins hands down—even to the point of the ani-
mal starving to death.32 When the effects of heroin are
compared with those of cocaine, the differences are
dramatic:
Those rats that self-administer heroin developed a
stable pattern of use, maintained their pretest
weight, continued good grooming behavior, and
tended to be in good health. Their mortality rate
was 36 percent after thirty days. Those self-
administering cocaine . . . exhibited an extremely
erratic pattern of use, with “binges” of heavy use

alternating with brief periods of abstinence. They
lost 47 percent of their body weight, ceased
grooming behavior, and maintained extremely
poor physical health. After thirty days, 90 percent
were dead.33
In the final analysis, from the st andpoint of
treating individuals who abuse drugs, it might not
matter whether there is physical depen-
dence or psychological dependence going
on. According to many experts in the field,
the distinction between physical and psy-
chological dependence has outgrown its
usefulness in explaining the motivation
behind drug abuse. Whether the discontin-
uation of an abused drug does induce major
physical withdrawal symptoms (as in the
case of heroin, alcohol, and barbiturates) or
does not (as in the case of cocaine, amphet-
amines, and nicotine), the patterns of com-
pulsive drug-taking behavior are remarkably
similar. If the pattern of behavior is similar,
then there can be common strategies for
treatment.34
A Final Note: Two
Perspectives on Drugs
and Drug Use
In order to understand the societal problems
associated with drug use and abuse, it is neces-
sary to examine these problems in terms of two major
perspectives. The first perspective, adopted primarily by
psychiatrists, psychologists, drug-abuse counselors, and

other health professionals, focuses on the adverse effects
of drug-taking behaviour on one’s physical health and
psychological well-being. In this regard, no distinction
is made with regard to the specific drug involved, only
its behavioural consequences. Legality or illegality is
not at issue. The second perspective, adopted primarily
by professionals in the area of criminal justice, focuses
on the specific drug being used. In this regard, drugs are
examined in terms of their accepted medical benefits,
their potential for abuse, and their legal status. The
implication for viewing drug-taking behavior from a
criminal-justice perspective is that drugs with the fewest
medical benefits and the greatest potential for abuse
should be the drugs with the most stringently restricted
availability, as established by law.
Drug-taking Behavior: The
Health Perspective
Most health professionals use guidelines published by
the American Psychiatric Association as an official stan-
dard for defining problems associated with drug-taking
behavior. Generally speaking, these problems, which
F I G U R E 1 . 4
A simplified rendition of how drugs are self-administered in
rats. The rat’s pressure on a lever causes the pump to inject a
drug through a catheter implanted into its vein.
Pump
Programming
equipment
Catheter

Lever
Drug
Levinthal.
Education.
G
A
R
R
E
T
T
,
M
E
G
A
N
1
3
2
4
T
S

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