1. health and fitness
2. addiction

2006
Cannabis-Marijuana:
Addiction,Treatment and Recovery
Published By Caron Treatment Centers
1
www.caron.org
About Caron Treatment Centers…
Caron Treatment Centers is a leading provider of
addiction treatment services in the fight against
chemical dependency. Caron uses a comprehensive
treatment approach incorporating spirituality, the
family, and current medical/psychological
interventions to help those affected by addiction
begin a life of recovery. Since its founding in 1957,
Caron has pioneered the concept of residential
codependency treatment, and currently offers
expertise in treatment services for adults, young
adults and adolescents. These services include:
early intervention, medical evaluation and
detoxification, primary and extended residential
treatment, relapse treatment, outpatient treatment
and family education.
Caron has responded to the continued demand for
addiction treatment services by offering facilities
in Wernersville, Pennsylvania, and Boca Raton,
Florida. Caron also has regional offices in New
York City and Philadelphia.
Caron’s mission is “to provide an enlightened, caring
treatment community in which all those affected by
alcoholism or other drug addiction may begin a new life.”
Table of Contents
5
Forward
6
Introduction: Addiction, Treatment & Recovery
6
What is Marijuana?
6
7
Cannabis Abuse and Addiction
7
8
Marijuana’s Actions and Effects
Symptoms of Addiction
Consequences of Cannabis Abuse and Addiction
9
Medical Consequences
9
Cognitive Impairment
9
Psychiatric Consequences
10 Social Development
10 Marijuana: A Gateway Drug?
11 Risks for Cannabis Addiction
11 Early and Heavy Marijuana Use
12 Marijuana and Nicotine
13 Gender Differences
13 Social Influences
14 Attitudes Toward Marijuana Use
15 Psychiatric Vulnerability
16 Treatment and Recovery
16 Seeking Treatment
16 Evidence-based Treatment for Adolescents
17 Evidence-based Treatment for Adults
17 Treatment Works!
19 Marijuana Dependence and Treatment at Caron
20 References
Forward
Hoover Adger, Jr., MD, MPH, MBA
Professor of Pediatrics
Johns Hopkins School of Medicine
arijuana is the most commonly used
illegal substance in the United States. Its
use is associated with educational
underachievement, reduced workplace
productivity, motor vehicle accidents, and
increased risk of use of other substances. While
current surveys document a steady decline since 1991
in the use of marijuana among youth, current rates are
still almost thirty percent higher than the nadir that
we experienced, in the early 1990’s, in the United
States. Even more concerning is the recent decline in
perceived risk and disapproval of use of marijuana by
our youngest individuals which may suggest a change
in the direction of recent progress that has been made
in this area.
M
Over the past two decades, scientists have further
substantiated the adverse effects associated with the
use of this drug. Cannabis-Marijuana: Addiction,
Treatment and Recovery, provides a thorough review
of what is known about the drug, the associated
consequences, and the evidence related to treatment
and recovery. In addition, data from the Caron
treatment and recovery experience further documents
and supports the emerging science related to
treatment for cannabis dependence.
The report does an excellent job of presenting an upto-date synthesis of information related to the adverse
health effects of cannabis abuse and addiction. Topics
addressed include: medical consequences, cognitive
impairment, psychiatric consequences and the impact
of cannabis use on social development. The data that
are presented highlight the recent concerns that have
been raised regarding impairment in short term
memory; the potential role of cannabis in injuries and
motor vehicle accidents; chronic bronchial
inflammatory changes and evidence suggesting a
causal role of cannabis smoking in upper airway
cancers in young adults. It also shows new information
suggesting a substantial involvement of cannabis
use in various psychiatric disorders including:
schizophrenia; depression; anxiety or panic disorders;
and behavioral disorders in young people; a causal link
to poor psychosocial outcomes among adolescents;
and new data supporting earlier evidence that
maternal use of cannabis during pregnancy may lead
to subtle but significant developmental problems in
offspring.
Important information is provided on risk factors for
addiction, marijuana and tobacco use, and gender
differences. This information is anchored by a
discussion of treatment and recovery and evidence in
support of treatment.
This is a well written and well researched article that
provides an impressive overview of the topic area and
should help the reader to have a much better
understanding of the most commonly used illicit drug
in the world, cannabis.
5
Marijuana:
Addiction,Treatment, and Recovery
THC usually is ingested by smoking it in handmade cigarettes,
is characterized by increases in the frequency of use and/or
water pipes, or regular pipes, and by consuming it in food or
amount of cannabis used, a preoccupation with use-related
drink. Recently, marijuana rolled in cigar wrappers called
activities, and an inability to cut down or control use despite
blunts has become popular. Marijuana is used alone or in
persistent physical, psychological, or social problems caused
combination with other drugs, nicotine, and alcohol.
or acerbated by its use. Physiological changes also can occur
When smoked, THC passes from the lungs to the bloodstream
and is carried to the brain, as well as other areas in our bodies.
to its effects and withdrawal symptoms upon cessation.
Smoking marijuana results in higher levels of THC in the blood.
Cannabis is recognized as a substance that can produce
ot, herb, weed, grass, ganja, hash and dope are some of
between 1956 to 1965 have used it.4 Since marijuana’s peak use
The effects are experienced within 10 minutes of smoking and
addiction. It is estimated that almost 10% of people who have
the many names for the most widely used illicit drug
in the 1960s, new users of marijuana have become younger and
last from one to three hours. Absorption into the bloodstream
ever used marijuana will develop an addiction.9 Approximately
in the world—cannabis. The hemp plant, cannabis
younger. In the 1960s and early 1970s, most users tried
is much slower when THC is consumed by mouth-within about
1% of the American population is estimated to meet diagnostic
sativa, produces two of the most commonly used
marijuana for the first time when they were over 18 years of age.
one-half to one hour-although the effects last as long as four or
criteria for cannabis addiction, including 2.6% of adolescents
illicit drugs—marijuana and hashish. Marijuana is a
However, in the mid to late 1970s, most new users were older
five hours.6 THC is easily stored in fat cells, and its slow release
and 3.5% of young adults, aged 18 to 25 years.5 Among American
dried mix of flowers, stems, seeds, and leaves of the hemp
adolescents, and since then most users tend to start marijuana
explains why traces of THC can be detected in chronic users
adults, rates of cannabis abuse and addiction have increased
plant. Hashish is the more resinous and concentrated form of
use in early to mid adolescence.5 More alarming was the rapid
for a week or much longer after consumption.
from 18% at the beginning of the 1990s to over 35% in the early
the hemp plant.
increase in daily use of marijuana among teens. By 1978 one in
P
Marijuana, hashish, and other forms of cannabis are potent
substances that alter mood, perceptions, and sensations. They
nine high school seniors (over 10%) reported they were using
Immediate effects of THC ingestion include rapid heartbeat,
marijuana for at least 20 days a month.3
relaxation, enlargement of the bronchial passages, and
expansion of blood vessels in the eyes.6 People also report an
also can become addictive and harmful. This report describes
altered state of consciousness and mild euphoria as THC
2000s.7 Cannabis addiction is also an issue for adolescents, and
the risk of them becoming addicted increases significantly in
later adolescence and early adulthood. A recent study in
Colorado found that a slightly higher proportion of adolescents
were diagnosed with cannabis addiction (4.3%) over alcoholism
the many aspects of cannabis use, including the extent of its
Marijuana’s Actions and Effects
activates the brain’s reward system. Users tend to experience
use, its psychoactive and addictive properties, consequences
Marijuana, hashish, and other forms of cannabis get their
pleasant sensations, colors, and sounds that become more
of prolonged use, risk factors for addiction, and treatment and
psychoactive properties from delta-9-tetrahydrocannabinol
intense, while perceptions of time and spatial awareness
recovery from cannabis use disorders.
(THC), a potent chemical found in cannabis. THC is found in all
become distorted. Motor skills and reaction time also are
The high rates of cannabis addiction can be seen in the
Although marijuana is one type of cannabis, this report will use
parts of the hemp plant, but is most concentrated in the
impaired. Feelings of hunger and thirst become pronounced,
prevalence of younger patients who are admitted to Caron for
marijuana for any type of cannabis use, and will use cannabis for
flowering tops of the plants and is least concentrated in the
and people often experience dry mouth. Following the initial
cannabis treatment. From January 2000 through June 2005,
cannabis disorders, such as abuse and addiction.
stems and seeds. Thus, the THC potency of marijuana tends to
euphoria, users can become tired or depressed, occasionally
almost 1,000 patients were admitted to Caron’s residential
range from .5% to 14% depending upon the parts of the plant
feel anxious or distrustful, or experience panic.
treatment program for cannabis addiction.11 As shown in Figure
used, growing conditions, and the plant’s genetic properties.
(3.5%), even though alcohol is more easily obtained than
marijuana and more often abused.10
1, over half of these patients were under 30 years of age.
What Is Marijuana?
Hashish, which is produced by extracting and drying resin from
Marijuana is the most widely used illicit drug in the United
the plant’s flowers, also varies in concentration of THC,
Cannabis Abuse and Addiction
Figure 1.
States, and over 50% of Americans report they have had an
although THC can be as high as 20%.6 Years of cultivation and
Cannabis abuse and dependence are psychiatric terms used to
Number of patients admitted to Caron for cannabis addiction, 2000-2005
opportunity to use the drug.1 Given the easy access to
plant breeding have increased THC potency dramatically. In
classify users by their severity of use and levels of
marijuana, most people who have the opportunity to try it, do
one decade between 1992 and 2002, the potency of THC
impairment.8 Abuse refers to repeated instances of use, or
so. In 2004, approximately 14.6 million Americans used
confiscated by law enforcement increased from 3% to 5%, an
recurring use, in hazardous situations, such as driving or
marijuana compared to only 2 million Americans who used
overall increase of 66%.7
operating machinery, despite significant social impairment
cocaine and less than 200,000 who used heroin. Additionally,
over 25 million Americans had histories of marijuana use.2
The actions of THC and other cannabinoid chemicals are
more than 60 unique chemicals found in cannabis. When THC is
each year, and approximately 1.3 million of these new users
isolated from the other cannabinoids, its effects can differ from
the condition of severe impairment due to chronic drug abuse.
are adolescents.
the effects produced when cannabis is consumed intact.
This report refers to dependence by its more commonly
The Monitoring the Future studies
conducted by the University of Michigan), which track student
drug use, have found that marijuana use among high school
students rose sharply in the mid 1990s to the late 1990s. Then
its use began to decline slightly among middle school and
high school students.3 Currently, almost half of high school
seniors report they have used marijuana at least one time, and
almost 6% use it daily.3
Marijuana did not attain its current popularity until the 1960s.
16-18 Years
(n=218)
30-55 Years
(n=404)
19-29 Years
(n=284)
accepted term—addiction. Dependence can be a confusing
In our brains, THC connects to specific nerve cells on sites
term because it is often thought of only in terms of physical
called cannabinoid receptors. These receptors are found in
dependence, such as a person’s tolerance for the drug and the
parts of the brain that regulate movement, coordination, and
person’s withdrawal symptoms when the drug is discontinued.
cognitive processes such as learning, memory, judgment,
A person can become dependent on (addicted to) a drug,
perception, and concentration. The cannabinoid receptors
including marijuana, without showing signs of physical
usually are regulated by endogenous cannabinoids that are
dependence. Physical dependence often occurs during proper
naturally found in our brains and have very similar chemical
medical use of certain medications, when other signs of drug
structures
dependence do not develop.
to THC. When
marijuana
is
used, THC
Under 16 Years
(n=30)
and interpersonal problems.
complex and are not completely understood.6 THC is only one of
Over 2 million Americans begin to experiment with marijuana
2
56 and Older
(n=49)
such as poor work or scholastic performance, legal problems,
Dependence is the psychiatric diagnostic term used to describe
(sponsored by the National Institute on Drug Abuse and
6
that affect how people respond to cannabis, such as tolerance
overstimulates the cannabinoid receptors and disrupts the
While only 2% of teenagers born between 1930 to 1940 have
normal connections between the receptors and our brain’s
Cannabis addiction results from continued use, and the
used the drug, approximately half of the teenagers born
natural endogenous cannabinoids.
addiction produces a number of negative behaviors. Addiction
Symptoms of Addiction
Two physiological characteristics of addiction are tolerance to
cannabis and withdrawal symptoms following abrupt cessation
of use. Tolerance occurs when a person’s response to a drug
decreases so that larger doses of the drug are required to
achieve the same effect. Tolerance is due to decreased
sensitivity to the drug as the result of repeated exposure. Both
biological processes and learning are believed to cause
7
Medical Consequences
In addition, even occasional use of marijuana can be
A number of harmful medical problems can be caused by
dangerous. Marijuana intoxication impairs attention, judgment,
chronic heavy marijuana use. Because marijuana is usually
coordination, short-term memory, and balance and can
smoked, it is not surprising that even light use can cause
increase the likelihood of accidents. In fact, up to 11% of fatal
respiratory problems, such as heavy coughing, irritation, and
accident victims test positive for marijuana.20 Almost one-
effects of euphoria and to avoid negative withdrawal symptoms.
stinging of the nose and throat. Frequent chest illnesses,
quarter of adolescents admitted to hospital emergency rooms
Marijuana appears to affect the brain in ways that are similar to
chronic bronchitis, and the risk of lung infections can occur
used marijuana.5 The National Highway Traffic Safety
from more severe use.
Administration found that a moderate amount of marijuana is
tolerance. Because tolerance limits the effects of the drug,
people generally experience withdrawal symptoms when they do
not increase the amount of drug needed to counteract the effects
Figure 2.
Aspects of marijuana cravings at admission
of tolerance. Thus, the development of tolerance generally leads
21
to higher levels of consumption of the drug to obtain the acute
15
other drugs, such as opiates, nicotine, and cocaine, and
Tolerance to the effects of marijuana is thought to be
influenced by the amount and chronicity of use, and the
individual differences in people’s biological sensitivity to
marijuana. Tolerance is less common in cannabis addiction
than in other drug addictions, such as addiction to alcohol and
sufficient to impair driving performance, and the combined
Craving
Levels
tolerance to the drug can develop with chronic heavy use.
9
either drug alone.20
contains irritants and carcinogens. Marijuana smoke contains
Emotionality
Expectancy
Purposefulness
Craving Factors
between 50% to 70% more cancer-causing agents than tobacco
3
choice long after withdrawal symptoms have subsided. People
with cannabis addiction who do not show signs of physical
smoke. Because marijuana smokers inhale deeply and hold
Psychiatric Consequences
their breath for a long time, they have increased exposure to the
High doses of, or the use of very potent marijuana can trigger
carcinogens. There is some evidence from human and animal
symptoms of panic, anxiety, psychosis, and depressed mood.25
studies that THC, the active component in marijuana, can
These symptoms generally subside as the psychoactive effects
impair the immune system and increase the risk of cancer.9
of the marijuana wear off.
Animal and clinical studies have also identified a withdrawal
dependence through tolerance or withdrawal symptoms can still
response. Abrupt cessation of chronic moderate to large
have cravings when they are abstinent from marijuana. For
In addition, people are more prone to heart attacks shortly after
Marijuana does not appear to cause psychiatric illnesses,
doses of marijuana can produce withdrawal symptoms.9
example, by the end of treatment, the severity of three types of
smoking marijuana than at other times because smoking
although it may precipitate a psychiatric episode in persons
Commonly reported cannabis withdrawal symptoms include
cravings—emotional
and
marijuana raises blood pressure and heart rate and at the same
who are predisposed to psychiatric illness. However,
decreased appetite and weight loss, irritability, nervousness or
purposefulness—significantly reduced for most patients at Caron,
time reduces the oxygen-carrying capacity of the blood. Chronic
despite this possibility, over 12% of American adults who
anxiety, anger and aggressive behavior, restlessness, and sleep
as did cravings overall. However, the uncontrollable compulsive
marijuana use also appears to increase the risk of stroke.
have tried marijuana suffer from a serious mental illness.26
disturbance with strange dreams. Some less commonly
aspect of craving remained high for some patients throughout
reported symptoms include depressed mood, stomach pain,
treatment. The sense of an uncontrollable need to use marijuana
13
chills, shakiness, and sweating.14 Cannabis withdrawal
relief,
positive
expectations,
can persist for a long time following withdrawal and treatment.
symptoms usually begin less than one day after stopping
People who are not strongly motivated to use “drug refusal skills”
marijuana use, and may produce significant discomfort lasting
that are learned in treatment can be vulnerable to relapse.
for one to four weeks.15 Withdrawal symptoms can be more
21
9
Pregnant women who use marijuana also can jeopardize fetal
development. Smoking marijuana during pregnancy is
associated with lower birth weight and shorter gestation
periods. Babies and young children born to women who smoke
marijuana during pregnancy often have more behavioral
People who begin to use marijuana in childhood are twice as
likely to have a serious mental illness, compared to people
who first try marijuana as young adults.26 As shown in Figure
3, almost 80% of patients who abuse marijuana experienced
symptoms of depression and/or anxiety in the month prior to
admission at Caron.18
Tolerance, withdrawal, and cravings all contribute to the
problems (such as not paying attention and impulsive
uncontrollable and compulsive drug seeking and using
behavior22) than other children who were not exposed to
Schizophrenia is a serious chronic mental illness that affects
Cravings for marijuana are reported by many users after
behaviors that are at the heart of addiction. A large sample of
marijuana before birth. Cognitive difficulties of marijuana-
about 1% of the population. It is characterized by symptoms
cessation.16 Cravings are a complex phenomenon with
Australian young adults revealed that the most commonly
exposed children include impaired learning and memory skills.
such as hearing voices not heard by others, believing other
subjective, behavioral, and physiological aspects. Cravings can
experienced symptoms of cannabis addiction were a persistent
be experienced differently depending upon the person’s
desire for marijuana, followed closely by uncontrolled use and
severe for people with psychiatric problems.
14
people have special powers over you, and disorganized speech
and behavior.8 The relationship between marijuana use and
withdrawal symptoms.19 These behaviors make it very difficult
Cognitive Impairment
schizophrenia is well documented. Young people diagnosed
for people to abstain successfully from marijuana.
Heavy marijuana use can impair short-term memory, attention,
with cannabis dependence have rates of psychotic symptoms
drug, the anticipation of relief from unpleasant emotions or
and coordination of movement. These cognitive impairments tend
that are over twice the rates of young people who are not
from withdrawal symptoms, the expectation of positive
to decrease with abstinence. However, the negative effects of
cannabis dependent.27
perceptions, physical state, or environment. Different types of
cravings include a compulsive uncontrollable need to use the
outcomes, or a state of purposeful planning to use the drug.
17
To learn more about cravings in cannabis addiction, we surveyed
a sample of 64 patients at Caron who reported marijuana abuse
in the month prior to admission, and resurveyed them during the
week prior to discharge.18 At admission, we asked patients about
their total level of cravings, and categorized cravings into four
types: compulsive use, emotional relief, positive expectations,
and purposefulness of plans to use marijuana.17 As you can see
in Figure 2, on average, patients experienced moderate levels of
each type of craving prior to treatment.
8
effects of marijuana and alcohol are much greater than for
cancer of the respiratory tract and lungs because the smoke
20
Compulsivity
heroin. Adolescents appear likely to develop tolerance even
though they use marijuana less frequently than adults.12
Marijuana smoke also can be related to the development of
Consequences of Cannabis Abuse and Addiction
marijuana on the brain can persist for heavy users. At 28 days
Chronic long-term use of marijuana can lead to a number of
following cessation of marijuana use, a sample of former users
harmful consequences. Persistent use has been shown to be
were given a battery of neurocognitive tests to assess their
harmful physically to users and to fetal development in pregnant
cognitive functioning. The heavy daily users tended to show
users. Heavy marijuana use also impairs cognitive functioning.
higher levels of impairment than the light users on tests
Prolonged and heavy use is related to the development of a
measuring memory, reasoning, visual perception, and motor skills.
number of psychiatric problems, including anxiety, depression,
and schizophrenia. Marijuana use also is linked to impediments
to social development, such as involvement in risky sexual
behaviors, poor academic performance, and an increase in
delinquency, crime, and violent behavior. Although the verdict is
Although cravings often occur when a person has stopped drug
still out regarding marijuana’s role as a “gateway” drug, we do
use, cravings are not symptoms of withdrawal. People in recovery
know that early use of marijuana puts young people at risk for
from drug addiction frequently experience cravings for their drug of
involvement with other drugs.
Figure 3.
Patients with symptoms of depression and anxiety
23
Neither
Depression
and Anxiety
Also, as people grow older, they naturally lose nerve cells in the
area of the brain responsible for short-term memory—the
Depression
hippocampus. The hippocampus has many cannabinoid nerve
cells, and long-term exposure to marijuana can quicken agerelated memory loss.20 A recent study found that people who
averaged 24 years of regular marijuana use performed much
Anxiety
poorer on tests of memory and attention than people who
averaged 10 years of use, or people who never used marijuana.24
9
However, the nature of the relationship has been controversial
Marijuana also has been found to have a negative impact on
and we do not know if schizophrenia leads to marijuana use, if
school performance. Early adolescent marijuana use decreases
marijuana use causes schizophrenia, if both conditions are
the likelihood of graduating from high school,29 and is
caused by something else, or if the relationship is more complex.
associated with problems at school.
A review of studies on the relationship between schizophrenia
and marijuana concluded that marijuana use doubles the risk of
developing schizophrenia, increases risk as greater amounts or
potency of marijuana are used, and results in a higher risk for
vulnerable people with a predisposition to schizophrenia.
28
Figure 5.
Male
Female
History of violent behavior
use to harder drugs. It is easier for adolescents to obtain
80
Regular and heavy marijuana use also is associated with
40
30
number of studies have found strong relationships between
social difficulties in adolescence and young adulthood. Young
marijuana use and violence. A major review of the scientific
marijuana users are at risk for other detrimental health behaviors
literature on marijuana and interpersonal violence21 found that
marijuana use is very common among men who are violent
toward their intimate partners. However, the review also states
crime, and heavy use can trigger violent behavior.
that scientifically controlled laboratory studies of violence and
Marijuana use is associated with unprotected sexual
marijuana are inconclusive.
intercourse, especially in adolescents. For example, a survey of
Moore and Stuart, the authors of the review, concluded that
a large inner-city sample of students found that early adolescent
marijuana use can trigger violent behavior in a number of
ways.21
First,
marijuana
20
10
0
Past Month
Violent Behavior
Percent
of patients
Lifetime
causes
cognitive
hard drug use by chronic marijuana users could explain why
chronic and heavy users of marijuana are more likely to progress
to harder drugs than are light and infrequent users.
Neither the marijuana gateway effect nor the common-factor
theory disproves the other. Both theories can explain the
these legal substances predicts an addiction to cannabis.
phenomenon of progression from initial marijuana use to
Adolescents who drink alcohol at least once a week are more
addiction to harder drugs such as cocaine and heroin. Social
likely than others to initiate marijuana use.36
environments in which marijuana is easily accessible and
Marijuana has long been considered a gateway drug leading to
intoxication
harder drugs.Third, increased availability and the acceptability of
the initiation of, abuse of, and addiction to drugs such as heroin
acceptable to young people could lead to early initiation of
marijuana use that becomes chronic for vulnerable individuals.
and cocaine. However, the designation of marijuana as a gateway
Chronic marijuana use could produce brain changes that lead to
drug is still controversial.
vulnerability to other drugs. Likewise, a predisposition to drug
addiction could lead young marijuana users to become chronic
impairments that can decrease the ability of a person to
Scientists who support marijuana as a gateway to harder drug
understand complex interpersonal conflictual interactions, and
use point to three types of evidence.31 First, marijuana users tend
can increase the likelihood of aggressive responses to conflict.
to have much higher risks for progression to other drug use than
Regardless of whether or not marijuana is shown to be the active
Also, intoxication increases heart rate, panic reactions, and
people who do not use marijuana, and the younger people are
agent that causes future addiction to harder drugs, we do know
As shown in Figure 4, the risk of unprotected sex continues into
paranoid feelings associated with violent behavior. Second,
when they begin to use marijuana, the more likely they will
that the use of marijuana introduces young people to a drug
adulthood for the 64 patients studied at Caron who were
withdrawal also can produce irritability and anger that can lead
progress to other drugs. This observation could support the
subculture that provides access to marijuana and promotes the
admitted for marijuana abuse and dependence.18 Over 90% of
to aggressive behavior.
premise that marijuana produces changes in a person’s brain that
use of other drugs.
Unprotected sexual behavior puts people at high risk for HIV
and AIDS, hepatitis C, and other sexually transmitted diseases.
Females are at risk for unplanned pregnancy.
adolescent
and
adult
patients
reported
prior
sexual
use drugs such as cocaine and heroin before they use marijuana.
dependence generally reported high levels of violent behavior.18
Instead, adolescents usually progress from marijuana use to the
As shown in Figure 5, similar percentages of male and female
use of harder drugs. Proponents of the gateway drug theory of
patients reported violent behavior in the month prior to
marijuana hypothesize that brain changes caused by chronic
admission and within their lifetime.
marijuana use make users vulnerable to further drug use. Third,
intercourse before they were 16 years old, and approximately
Most people who are intoxicated with, or in withdrawal from,
there is a strong relationship between the frequency of marijuana
50% had at least six sexual partners in their lifetimes.
marijuana do not become violent, and many people become
use and the risk of addiction to other drugs. Chronic and heavy
violent when they are not under the influence of marijuana.
users of marijuana are more likely to progress to harder drugs
Violent behavior can be related to personal histories of
than are light and infrequent users, lending support to the
violence, temperament, psychiatric disorders, the immediate
hypothesis that marijuana produces changes in the brain that can
risky sexual behaviors than did the adults, although no
statistical differences in use of drugs and alcohol with sex and
use of condoms were found between the groups. Half of the
Caron patients reported they first engaged in sexual
Figure 4.
Adolescent
Adult
Risky sexual behaviors
Sexual Intercourse
Drugs, Alcohol & Sex
Condoms & Sex
marijuana; use of nicotine; male gender; social influences and
relationships with other people who use drugs and alcohol;
attitudes toward drug use; and psychiatric vulnerability. Risk
factors have a cumulative effect and addiction generally does
not occur without warning signs.
A powerful risk factor for cannabis addiction is early initiation to
differently to support a common-factor theory of how marijuana
marijuana. The younger the person is when he or she first tries
and initiation to other drug use are related.31 Under the common-
marijuana, the more likely he or she is to become addicted to it. A
factor theory, marijuana addiction and addiction to harder drugs
long-term study found that students who began using marijuana
“Gateway drug” is a term used to describe a drug that is
are hypothesized to be due to a combination of genetic
in elementary school were four times as likely to use the drug in
supposed to lead to the abuse of other more dangerous drugs.
predisposition (an underlying tendency) toward drug use and
middle school than students who did not initiate use in
The gateway drug effect is based on the premise that something
environmental influences.
childhood.32
produces long-lasting changes that cause progression to the
The common-factor theory counters the gateway effect in the
In addition, early initiation to marijuana is related to a number of
abuse of more dangerous and addictive drugs. Tobacco and
following ways. First, underlying genetic vulnerability to addiction
other negative consequences. First use of marijuana at an early
alcohol are gateway drugs to marijuana use, and underage use of
in general—not brain changes caused by the marijuana—could
age increases the risk of becoming delinquent, engaging in sexual
80
Marijuana: A Gateway Drug?
Percent
of patients
factors. These risk factors include early and heavy abuse of
Early and Heavy Marijuana Abuse
90
60
50
40
30
20
10
0
Most people who develop addictions have a number of risk
However, the evidence of a gateway effect can be explained
intoxication or withdrawal.
70
Risks for Cannabis Addiction
lead to other drug abuse and addiction.
setting, and a sense of threat,21 and not necessarily related to
100
users who are more likely to experience these brain changes.
promote further drug use. Second, adolescents rarely begin to
Patients in treatment at Caron for cannabis abuse and
intercourse. Surprisingly, the adolescent patients reported less
10
enter a drug subculture that offers more opportunities to try
50
found that young people who reported at least weekly
Regular or heavy marijuana use is associated with a range of
vulnerable to drug addiction progress to harder drugs as they
60
followed over 1,000 New Zealanders for their first 21 years of life
Marijuana use also might promote interpersonal violence, and a
multiple sexual partners and not always using condoms.29
is acceptable to use marijuana. Some adolescents who are
juvenile delinquency, crime, and violent behavior. A study30 that
Social Development
marijuana use increased the risk five years later of having
marijuana over other drugs, and adolescents generally believe it
70
crimes and in crimes against property.
become dependent on marijuana are at risk for delinquency and
interaction between environment and genetic vulnerability could
explain why drug use generally progresses from initial marijuana
marijuana use had an increased risk of engaging in violent
and for poor academic performance. People who abuse or who
account for marijuana use leading to harder drug use. Second, an
intrinsic to the gateway drug, such as the way it affects the brain,
11
risk behaviors, using other illicit drugs, having friends who also
exhibit deviant behavior, and not graduating from high school.29
Figure 7.
Figure 8.
Figure 9.
Tobacco and marijuana use
Mixing nicotine and marijuana in blunts
Gender differences in cannabis addiction admissions
Early initiation into marijuana use can increase the risk of
Always
developing an addiction to cannabis because people who begin
50
100
Often
to use marijuana at young ages also are likely to use it in a
compulsive way and become out of control more frequently than
40
80
Never
users of alcohol. For example, one study found that even once33
Male
Female
33
30
60
a-week use predicted later development of cannabis addiction.
Adolescents seem to develop the symptoms of addiction to
40
Percent
of patients
Sometimes
20
Percent
of Cannabis
Admissions
cannabis at a lower frequency and amount of use than do adults.34
As shown in Figure 6, patients admitted to Caron for cannabis
addiction, report a high frequency of use.18 Over three-quarters of
these patients reported using marijuana 14 or more days in the
Daily Tobacco Use
10
Under 16
20
Lifetime Tobacco Use
16-18
0
19-29
Rarely
0
30-55
Always Smoke Tobacco and Marijuana
Age Group
56+
month prior to admission, and over half reported daily use.
Frequency of nicotine use does not seem to be related to later
The higher prevalence of male marijuana use appears to be
cannabis dependence. Instead, nicotine use appears to be
related to opportunities to try the drug. Male adolescents
related to a social environment that promotes underage use of
appear to have more opportunities to be introduced to
It is possible that the higher rates of tobacco use found in our
legal substances33 and to adult use of nicotine. Adolescents
marijuana than do female adolescents.1 However, given the
residential sample reflect higher levels of psychosocial problems
whose fathers smoke tobacco are at greater risk than other
opportunity to use the drug, females seem just as likely as
than those found in outpatient populations. A survey of cannabis-
adolescents to begin to use marijuana.
males to try it. Interestingly, females are more likely to become
Figure 6.
quarters of these patients report they always smoke tobacco
Frequency of marijuana use in month prior to admission
when they smoke marijuana.
Less than 7 Days
7-11 Days
addicted patients admitted to outpatient treatment found that
tobacco smokers had higher psychiatric severity, a greater number
of legal problems, lower education levels, and lower incomes than
28 or More Days
non-tobacco smokers.39 Tobacco smoking also was related to
earlier age of initiation to marijuana and greater alcohol severity.
43
Marijuana also could be a gateway to nicotine use, especially for
addicted at lower levels of use than are males.34
people who smoke blunts. Marijuana use also reinforces nicotine
Females also are more likely to use tobacco prior to their
use because both substances are inhaled by taking smoke into
introduction to marijuana, while males are more likely to
the lungs. Smoking either substance (or both together in a blunt)
precede marijuana use with alcohol.42 In fact, female
can become a trigger to use the other one. Thus, continued use of
adolescents are more likely to develop an addiction to nicotine,
Marijuana and nicotine use generally are combined by alternating
one substance can make it more difficult to abstain from using
compared to male adolescents who are more likely to become
puffs of cigarettes and joints (marijuana cigarettes). Recently, in
the other one. Marijuana users can experience greater difficulty
addicted to alcohol and cannabis.
Delaying marijuana use might not be sufficient to reduce the
the United States, the use of “blunts” have become popular
quitting nicotine than nonusers. In fact, a number of marijuana
negative consequences of use. One study found that
among some groups of marijuana users. Blunts are tobacco
users who have been interviewed about their nicotine use report
adolescents who started marijuana use after the age of 13, but
leaves or cigar wrappers filled with marijuana. Gutted-out cigars
they have tried to quit tobacco but were not able to stop its use.44
who steadily increased their use throughout adolescence and
also are used to contain marijuana. Other drugs, such as heroin,
Early initiation and heavy use of marijuana, and the use of
young adulthood, were more likely to use other illicit drugs than
cocaine, PCP, methamphetamine, and embalming fluid, also can
nicotine, alcohol, and other drugs are strongly related to social
adolescents who started marijuana use younger than 13, but
be added to blunts to achieve different effects. The use of blunts
Gender Differences
influences. These influencing factors include families, friends,
who did not increase their use over time.35 High frequency use
has been related to increases in emergency room and drug
Modest gender differences have been found in the initiation to,
and scholastic performance.
could be due to social and psychological reinforcers of drug-
treatment admissions. Male adolescents are more likely to use
and heavy use of, marijuana. In general, males and females are
taking behavior and to the addictive properties of the drug itself.
blunts than females, and blunt use also is associated with poor
more alike than different in their use of marijuana. However,
scholastic achievement, belonging to a single-parent family, non-
surveys have found that males appear slightly more likely to use
white race, and use of both cigarettes and cigars.41
marijuana than females, and more likely to develop an addiction
14-25 Days
Marijuana and Nicotine
40
to it. While over 7% of male high school seniors reported using
Social Influences
Most of us begin our lives within a family unit that can vary from
a single-parent to a multigenerational extended family unit. The
people who raise us from birth through young adulthood have a
profound and lasting influence on our development. Parents
can influence future marijuana use and can become a
People who smoke tobacco are more likely to use marijuana
Although use of blunts has become more common, it probably is
marijuana on a daily basis in 2004, only 3% of female seniors
than those who do not smoke tobacco, and nicotine use often
not the most common method of using marijuana. As seen in
reported daily use.3
precedes marijuana use. However, recent research suggests
Figure 8, very few Caron patients report they always mix tobacco
that marijuana also might serve as a gateway to tobacco use.38
and marijuana in a blunt.18 In fact, over two-thirds of Caron
As shown in Figure 9, gender interacts with age in patients
bond are less likely to begin to use marijuana than are those
patients either rarely or never mix tobacco and marijuana.
admitted for cannabis addiction at Caron. From 2000 to mid
who do not emulate their parents.43 On the other hand, parental
37
Either way, smoking both substances increases health risks and
protection against abusive drug use. For example, children who
identify with their parents and who experience a strong family
11
2005, almost 62% of patients admitted for cannabis addiction
drug and alcohol use and family conflict predict marijuana
As mentioned above, tobacco use often is a precursor of
were male. However, gender differences do not appear until
use.43,45,46 Parents who set, monitor, and enforce reasonable rules
Surveys of cannabis-addicted patients in outpatient treatment
marijuana use and can be a risk factor for cannabis addiction.
young adulthood, when Caron generally admits a higher
and limitations also tend to protect their children against early
have found that approximately 50% of the patients also smoke
The earlier children begin to use legal substances such as
proportion of male cannabis-addicted patients than female
initiation to marijuana. In addition, the family value of religious
tobacco.39 As shown in Figure 7, patients in treatment for a
tobacco and alcohol, the more likely they will turn to illicit drugs
patients. Although slightly more young adolescent, middle-
attendance also serves as a protective factor against early
marijuana disorder at Caron have much higher rates of
such as marijuana. Older adolescents who began smoking
aged, and older females are admitted for cannabis addiction
marijuana initiation. Siblings, one’s sisters and brothers, also
marijuana and nicotine use.18 Over 95% of the patients reported
tobacco before the age of 13 are more than three times as likely
than males in those age groups, gender differences are not as
are important influences. Sibling alcohol use also predicts
they have used a tobacco product in their lifetime, and over 80%
to have used marijuana than those who did not smoke.42
pronounced as for the younger adult group.
marijuana initiation.43
can lead to greater rates of addiction to nicotine and marijuana.
smoke cigarettes on a daily basis. In addition, more than three12
13
Peers are our contemporaries and usually are defined as
do not hold part-time jobs or who work fewer hours.51 Students
frequently expect positive consequences, such as feelings of
people who are similar to us. Peers make up the friendship
who work can have extra money to spend on drugs. They also
relaxation, mind expansion, and social enjoyment.54 Furthermore,
networks of adolescents. A hallmark of adolescence is the
could be less committed to school and spend less time on
the belief that marijuana will produce relief from negative moods
importance of peer culture—or the values and expectations of
schoolwork. As shown in Figure 10, less than 10% of the
tends to be associated with cannabis addiction.55
friends. Although parents remain important throughout life,
adolescents in treatment at Caron for cannabis disorders report
peers become more important to adolescents and often
they do not work, and almost 20% work more than 20 hours a week.
overtake parental values as people mature.
patients is the motive to use marijuana for enjoyment and to get
commitment—unites the social predictors of cannabis
“high.”18 The other motives for using marijuana appear to be
factor in adolescent initiation to marijuana use and the
addiction.52 People who become addicted to cannabis are less
less important to these patients. One of their treatment goals
development of cannabis addiction. Adolescents are strongly
committed to family, religion, and school than others. They also
will be to find other more appropriate ways to enjoy themselves
show a higher commitment to deviant peer groups.
marijuana and who have positive attitudes toward marijuana
are more likely to initiate use themselves.47 Characteristics of
these peer groups also include other deviant behaviors such as
underage alcohol and tobacco use and delinquency.
besides using marijuana.
Figure 11.
Motives for marijuana use
Attitudes Toward Marijuana Use
Attitudes toward marijuana and the availability of marijuana are
adolescents who are susceptible to cannabis abuse select peer
marijuana or who is unable to obtain it. From 1975 through 1978 the
groups that have favorable attitudes toward the drug and use it.
perceptions of harm from marijuana decreased among high school
Friends, however, remain a strong influence on a person’s
marijuana use. The negative attitudes of one’s friends toward
marijuana use strongly influence a person’s likelihood to stop
development of sober and abstinent friends and peer groups.
5
Percent
of patients
0
disorder preceded or was the result of chronic marijuana use.
Recent long-term research has found that a depressed mood
Enjoyment & “High”
often precedes initiation to marijuana, indicating that
students. During the late 1970s and throughout the 1980s the
Be Sociable
depression is a risk factor for marijuana use.9
perception of harm increased as the use of marijuana dramatically
decreased. However, in the early 1990s perceived risk again began
People who are victims of violence, such as physical or sexual
Cope with Negative Mood
to drop, again followed by an increase in use. These national data
1
show that attitudes about marijuana precede changes in its use.
6
assault, or who have witnessed violence toward others are at
11
16
21
Average Score
an increased risk of developing posttraumatic stress disorder
(PTSD), a psychiatric condition related to the experience of
On the other hand, peers are a major source of marijuana,
The increase in positive attitudes toward marijuana use that
especially for adolescents. Over 80% of adolescents obtain
resumed in the 1990s could be due to a number of events.3 A
decrease in media coverage of the harmful effects of the drug,
Psychiatric Vulnerability
of marijuana use.58
their marijuana from a friend, either for free or purchase.49
a decrease in anti-drug advertisements, and a decrease in
As discussed earlier in the Psychiatric Consequences
Sensation seeking is a type of behavior in which people are
funding for drug abuse prevention programs in schools, all
section, we have seen that marijuana can trigger a psychiatric
drawn to novel, often risky and dangerous, experiences.
occurred during this period. At the same time, popular music
disorder in people predisposed to it. Psychiatric disorders also
Sensation seeking is a trait embedded in our biological
groups began to highlight “positive” aspects of marijuana in
appear to increase the risk of marijuana use. Psychological
makeup, and high-sensation seekers have brain differences
their music. Additionally, it is possible that parents who came
predictors of marijuana use include poor control of emotions,
that can reduce normal levels of stimulation. People with high
of age in the 1960s during the earlier surge of marijuana use
depression, anxiety, poor coping skills, low self-concept,
sensation seeking needs appear to receive stimulation directly
might not have known how to tell their children to avoid drugs.
deviance, rebelliousness, and an inability to be empathetic
from drugs like marijuana, and also receive stimulation from
Interestingly, part-time employment during high school also is
New educational initiatives and decreases in media
with others.46 Psychiatric conditions, such as depression,
being part of an illicit drug culture.59 Sensation seeking
associated with marijuana use. Students who work between 26 to
glorification of drug use could trigger a trend toward an
posttraumatic stress disorder, and conduct and antisocial
behaviors among young adolescents have been found to predict
31 hours a week are more likely to use marijuana than those who
increase in the appreciation of the risks of marijuana.
personality disorders have been found to precede and predict
increases in marijuana use.60
Figure 10.
People who hold positive attitudes toward drug use also might
Adolescent employment status
misperceive the prevalence of drug use among their friends. For
High rates of psychiatric problems have been found among
activities.The psychological condition for this type of behavior is
example, college students who use marijuana believe that
people who are addicted to cannabis. Approximately 90% of this
known as a conduct disorder or antisocial personality disorder.
marijuana use on their campus is higher than is actually
population has experienced a psychiatric illness during their
Children and adolescents are the main populations diagnosed
reported. Thus, although peers are significant predictors of
lifetime.57 Rates of psychiatric illness also are high for patients
with conduct disorder, and young adults are the population most
marijuana use, use of the drug also can change a person’s
admitted to Caron who have used marijuana in the month prior
often diagnosed with antisocial personality disorder. It is widely
perceptions about peer group use.
to treatment.18 As shown in Figure 12, over 15% of these patients
recognized that adolescents who engage in problem behaviors,
report they were treated at least one time in an inpatient
such as delinquency, gang membership, aggression, and early
Attitudes toward marijuana use influence initiation to the drug,
psychiatric hospital, and over 12% receive a pension for a
sexual activity, are also likely to use marijuana. Although
but do not explain the development of addiction. Addiction could
psychiatric disability. More than 23% of these patients have
antisocial behavior can follow initiation to drug use, antisocial
be more strongly related to a person’s motives for using the drug.
experienced suicidal thoughts in their lifetime, and over 10%
behaviors also have been shown to precede and predict later
People who do not use the drug and who hold negative attitudes
have tried to commit suicide. In addition, over 62% of the
marijuana use. For example, one study found that antisocial
toward marijuana also expect that its use will result in negative
patients are prescribed a psychiatric medication, and more
behaviors displayed by 9- and 10-year-old children were the best
consequences. Alternatively, people who use marijuana
than 73% have experienced serious depression or anxiety.
predictor of marijuana and alcohol use in adolescence.61
Initiation to marijuana use also is predicted by poor academic
performance. Adolescents who earn grades of C or lower have
twice the risk of starting marijuana use in the next year
compared to those whose grades are higher.50 In addition to
poor academic performance, school-related predictors include
truancy and school dropout.
traumatic events. PTSD has been found to increase the risk
future marijuana use.
20-31
Hours/Week
Unemployed
53
10-19
Hours/Week
Irregular Hours
14
10
Inpatient
Psychiatric Treatment
Psychiatric Pension
Lifetime Suicidal Thoughts
Lifetime Suicidal Attempt
disorder. However, we have been uncertain whether the mood
Conformity
3
marijuana use.48 One of the major tasks of early recovery is the
15
use and mood disorders such as depression and bipolar
approves of marijuana use and who has easy access to the drug is
much more likely to use it than a person who disapproves of
20
Clinicians have long been aware of a link between marijuana
Expand Awareness
important predictors of subsequent marijuana use. A person who
Adolescents choose their peer groups and friends. Most likely,
25
Marijuana Motives Measure56 (on a scale from 1-25) for Caron
An underlying theme of commitment—including lack of
regarding drug use. Adolescents with friends who use
History of psychiatric distress
As shown in Figure 11, the highest average score on the
Peer culture has been found to be an especially important
influenced by the attitude and behaviors of their friends
Figure 12.
Sensation seeking often is related to deviant and illegal
15
Treatment and Recovery
In addition, adolescents are not free to change their living
Because adolescents are embedded in their families, treating the
Reward-based treatments often involve the use of vouchers as
It takes more than willpower to recover from an addiction.
arrangements, but often are embedded in dysfunctional family
entire family instead of concentrating be solely or mainly on the
rewards for the achievement of a treatment goal such as
Recovery requires a high level of motivation and the
systems. Therefore, a major component of adolescent treatment
adolescent can be valuable and useful. The Family Support
attending sessions or abstaining from drug use. Vouchers
development of a new set of skills to avoid and abstain from
is a focus on the family unit, with goals of increasing positive and
Network (FSN) was developed specifically for the Cannabis Youth
usually have a monetary value and can be redeemed for goods
drugs. Often people must make significant changes in their
effective family management and decreasing conflict and poor
Treatment Study. It is designed to enhance family communication,
or services selected by the participant such as entertainment
lifestyles to maintain their recovery. Treatment programs offer
communication. Adult treatment programs, on the other hand,
improve parental behavioral management skills, and increase
admissions, recreational equipment, or educational or
clinical expertise and experience to facilitate recovery.
can focus more on employment skills and adult relationships.
family commitment to the recovery process. In addition to
vocational classes. Adding abstinence-based vouchers to
separate treatment (such as CBT or MET) for the adolescent,
other behavioral treatment for cannabis addiction has been
parents receive educational sessions that focus on adolescent
shown to improve marijuana abstinence rates compared to
development, drug use, and family management. Parents also
providing behavioral treatment alone.72
Recently, innovative treatment strategies for adolescents and
adults have been tested in academic and community treatment
A number of treatment strategies for cannabis addiction have
been rigorously tested in clinical trials. A clinical trial compares
settings. Many of these evidence-based treatment approaches
one or more treatments against each other. Generally, patients
have been incorporated into residential and outpatient
who volunteer to take part in a clinical trial are randomly assigned
treatment programs, such as Caron Treatment Centers. Overall,
to a treatment group in order to minimize differences between the
evaluations of treatment programs and strategies find that
groups. Treatments that tend to produce good outcomes, such as
treatment works! People with serious addictions to drugs, such
lowering
practicing their skills. Group educational sessions also foster the
development of support networks for parents.
Brief marijuana dependence counseling (BMDC) was designed
to address the multiple addiction, psychological, and social
needs of adults who are addicted to cannabis.73 BMDC
raising
Another family-based approach that has been studied in the
combines interventions to increase motivation, and case
as marijuana, generally benefit from treatment in a number of
psychosocial functioning, are called evidence-based treatments
Cannabis Youth Treatment Study is multidimensional family
management to increase the patient’s ability to receive
areas of functioning, including the main problem of addiction.
because they have at least one study attesting to their efficacy.
therapy (MDFT).68 MDFT was developed specifically for the
necessary treatment for non-substance-related problems, and
treatment of adolescents with substance-use disorders.
cognitive behavioral skills to abstain from marijuana. Unlike
Treatment focuses on the adolescent, the parents, family
other research-based treatments that require rigid adherence
communication patterns, and community system involvements
to a specific protocol, BMDC is designed to be flexible and to
such as juvenile justice or school systems. Treatment focuses
meet the individual needs of different patients.
posttreatment
use
of
marijuana
and
Since there are no pharmacological treatment interventions for
Seeking Treatment
marijuana that are supported by clinical trials, the available
The 1990s saw a dramatic rise in the use of marijuana and
evidence-based treatments use psychological and behavioral
initiation beginning at young ages. Currently, marijuana is the
methods. In addition, these treatments have been specifically
primary substance of abuse for 47% of adolescents admitted to
designed either for adult or adolescent populations.
publicly funded addiction treatment programs,62 and the
generation of new marijuana users could increase future
demands for adult addiction treatment. If current rates of
Evidence-Based Treatment for Adolescents
marijuana initiation continue, it has been estimated that the
As mentioned earlier, adolescents often have low motivation
need for treatment will increase by 57% by 2020.63
for recovery. Motivational enhancement therapy (MET) is
People tend to enter addiction treatment because they, or people
close to them, recognize negative consequences of their drug
use and are unable to abstain from using drugs or alcohol on
their own. The severity of cannabis addiction is not necessarily a
predictor of seeking treatment. Adults who are addicted to
cannabis and who have been treated previously, or who are
alcoholic and depressed, are likely to seek professional help
regardless of the severity.64 How parents and the child perceive
cannabis addiction predicts adolescent engagement in
treatment. Parents who have positive expectations for their
16
receive home visits for the purpose of individualizing and
on the establishment of a therapeutic alliance with all members
of the family and community systems, assessment of family
functioning, and therapeutic activities to promote positive
Treatment Works!
changes in individual, family and social systems and how they
Scientific and clinical evidence strongly indicate that treatment
have influenced the adolescent. MDFT combines individual
works for a majority of people with cannabis use disorders. A
sessions with the adolescent or parents with family sessions.
large evaluation of over 1000 adolescents who received either
designed to increase motivation. Therapists who use MET are
Acknowledgements and rewards are useful motivations for
trained in empathic listening and accurate reflection of their
people, and especially adolescents, to change their behavior. In
patients. Instead of confrontation, MET’s goal is to make the
the adolescent community reinforcement approach (ACRA),
patient feel understood. MET therapists are not passive. They
therapists help adolescents connect to positive social and
actively reflect on discrepancies between the patient’s goals
recreational activities, and teach skills to refuse drugs. Parents
and behaviors in order to motivate the patient to take
are included in the treatment process. ACRA was used as an
responsibility for change. MET was developed for use with
outpatient treatment as part of the Cannabis Youth Treatment
adults,66 and was adapted for use with adolescents in the
Cannabis Youth Treatment Study.67, 68 The study was designed to
look at five different treatment interventions and develop
child, or who are aware of their child’s deviant behaviors, are
evidence-based manuals that could serve as models for the
likely to seek treatment. It also found that these adolescents
treatment field for adolescents.
reported high levels of family conflict.65
Another treatment that was combined with MET in the Cannabis
Adult and adolescent treatment programs should address the
Youth Treatment Study is cognitive behavioral therapy (CBT).
skills and lifestyle changes necessary to attain and maintain
CBT was developed in the 1970s as a psychotherapeutic
abstinence, and should address psychiatric, relationship, legal,
approach that promotes effective ways of thinking and behaving.
and medical problems, when necessary. However, adolescents
It was adapted for use in the adult treatment of addictions,69 and
and adults differ in their treatment needs. Adolescents tend to
was recently adapted and studied as part of the Cannabis Youth
be less motivated than adults to want treatment and tend to
Treatment Study. CBT helps patients to identify dysfunctional
drop out of treatment prematurely if it is not designed to meet
ways of thinking and to replace those thought patterns with more
their needs. Thus, adolescent treatment programs should have
productive cognitions. CBT also emphasizes skill development
age-specific strategies to motivate young patients. These
as patients learn effective strategies to avoid drug-use
programs also need to address academic-related problems and
situations and to refuse drugs. Therapists teach these skills in
peer groups, because both of these factors predict continued
individual or group sessions through the use of brief lectures,
use of the drug and relapse for adolescents.
role-playing, homework, and other exercises.
Study.68 A similar, but more intensive outpatient aftercare
program known as Assertive Continuing Care was developed
for youth following discharge from inpatient or residential
treatment.70 This treatment approach combines ACRA with
case management to assure the adolescents receive necessary
community services. It is very similar to Caron’s successful
Recovery Care Management aftercare program.
residential, outpatient or short-term inpatient treatment found
that less than half of the youngsters reported marijuana use in
the year following treatment.74 This study, known as the Drug
Abuse Treatment Outcomes Study for Adolescents (DATOSA), also found sharp decreases in heavy drinking, use of other
illegal drugs, and delinquent behavior. Adolescents who
received treatment also reported better school performance
and psychological adjustment following treatment. The results
of this study are especially impressive given the adolescents
had multiple and severe psychological and social problems and
were not an “easy” group of youngsters to treat. Similarly, a
review of the literature on the treatment of cannabis addiction
found that adults generally improve with treatment.75
Longer-term treatment and treatment that individualizes a variety
of therapeutic approaches to meet the needs of specific patients
appears to be more beneficial than short-term treatments or rigid
Evidence-Based Treatment for Adults
single-approach interventions. DATOS-A found that adolescents
A number of treatments have been developed and tested for adult
cannabis
addiction.
Cognitive
behavioral,
motivational
enhancement, support groups, and reward-based treatments have
demonstrated success in reducing marijuana use. A combination
who stayed in treatment longer were more likely to maintain the
positive benefits of treatment one year later, regardless of the
severity of their addiction and other psychosocial problems.74
of treatments appears to be more helpful than any single
Benefits of treatment may appear during the course of a
treatment type. For example, a clinical trial found that motivational
treatment episode. Motivation, craving, and psychological
enhancement therapy (MET) combined with cognitive behavioral
functioning are important predictors of successful addiction
therapy (CBT) and case management produce better results than
treatment. Patients who abuse or who are addicted to cannabis
a brief motivational enhancement approach.71
were assessed for their levels of motivation,76 cravings for
17
marijuana,17 and depressive symptoms77 at admission and prior
to discharge from Caron. As shown in Figures 13, 14, and 15, we
Marijuana Dependence and
Treatment at Caron
Figure 15.
Depression change in treatment
found significant positive changes in these areas during the
16
course of treatment.
14
Figure 13 shows that patients generally acknowledged low
Admission
12
recognition that they have a serious problem with marijuana
10
upon admission to a Caron residential treatment program. By
the time they are ready to be discharged, their awareness that
Discharge
harm will continue if they do not change their behavior has
8
6
significantly increased. Likewise, upon admission, patients
4
generally report a moderate willingness to take the changes
necessary to stop their marijuana use. However, by discharge
Average
Score
David Rotenberg, MA, MBA, CAC Diplomate
Executive Director, Caron Adolescent Services
Caron Treatment Centers
2
they generally report they have begun to take steps to change
their behavior and they have experienced some success.
Recognition
Taking Steps
Figure 13.
Motivational change in treatment
Popular culture has long considered marijuana to be a “benign”
recreational drug. However, this report shows the negative
impact that marijuana use can have on people’s lives. It may
40
cause severe physical and cognitive damage and may trigger
38
psychiatric illness in vulnerable populations. Chronic and high
use may lead to cannabis addiction.
36
Admission
Discharge
34
Cannabis abuse and addiction are related to a decreased ability
to function in a number of areas. People who abuse cannabis
32
Average
Score 30
generally abuse other substances, like underage alcohol and
nicotine use. They may be introduced to part of a drug abuse
28
subculture that promotes other deviant behaviors, like
26
delinquency, crime and use of other illicit drugs.
24
Treatment provides hope for this population.The past decade has
witnessed advancements in treatment approaches. Two major
As shown in Figure 14, patients admitted to Caron for cannabis
disorders generally have moderate levels of cravings.
Generally, marijuana-related cravings significantly decrease
studies of treatments designed specifically for cannabis
addiction, the adult Marijuana Treatment Project71 and the
adolescent CannabisYouthTreatment Study,68 have demonstrated
the effectiveness of treatment.
during the course of treatment.
Psychiatric functioning also improves during the course of
treatment. As shown in Figure 15, patients generally enter
treatment at Caron with moderate levels of depressive
symptoms. By discharge, however, their symptoms usually are
Similar to the successful treatment of other addictions, treatment
for cannabis addiction needs to be individualized to the specific
needs of each patient. Motivation should be addressed when
patients are not interested in change. Skill development should be
tailored to patients’ strengths and circumstances. Family
within the normal range.
involvement and family education may enhance the treatment of
adolescents and adults who are embedded in family relationships.
Figure 14.
Attention also must be paid to the medical, psychological and
Craving change in treatment
social needs of this population. Longer treatments also appear to
46
be more effective than very brief approaches. And, perhaps most
44
importantly, patients should not be forgotten when they are
42
discharged from a treatment program. Aftercare that continues to
Admission
40
monitor and engage the patient in recovery-oriented activities
38
facilitates change from addiction to recovery.
36
34
Discharge
32
30
18
Average
Score
espite the fact that oxycontin, methamphetamine and a variety of prescription drugs
seem to garner the bulk of the media’s, and
the chemical dependency treatment field’s
attention lately, marijuana remains the drug
of choice for adolescents and young adults in America.
At Caron, our clinical team has embraced the fact that
not only does marijuana remain popular, but it is also
viewed in an “ever-more-benign” fashion by our
patients. Furthermore, marijuana is not only perceived
as a “soft” drug by our patients, but also, perhaps for the
first time, by the parents of our young patients, as well.
and their ongoing right to use it, as enthusiastically as
a crack addict or heroin addict chase their next fix.
“It took my motivation. It made me fall from an A
student to a C student. I quit all of my sports teams. I
stopped playing music and doing art. I became very
distant from my parents and the rest of my family. I
changed my friends. I stopped paying close attention
to my personal hygiene.” Does this series of
statements describe an alcoholic or heroin addict?
Hardly. This series of quotes describes the impact of
chronic marijuana usage on our patient population.
Despite the devastating truth inherent in these
quotes, our patients continue to distance marijuana
from other “hard” drugs. In many cases, however, the
only difference between the use of “hard” drugs and
marijuana is physical withdrawal symptoms.
Nevertheless, marijuana users protect their drug,
their perception of its “benign” impact on their lives,
loopholes to maintain chemical usage and related
D
Our clinical staff at Caron understands the cultural
viewpoint of America’s youth, and its embrace of
marijuana, not as a gateway drug, but as a rite of
passage and as an accepted part of young peoples’
behavioral repertoire. We understand the skewed logic
that applies when patients with chemical dependency
differentiate themselves and their drug of choice from
the norm. We understand that the chemically dependent
population, and particularly the younger portion of this
population, will consistently seek gray areas and
abhorrent behavior. We assist patients in identifying
marijuana as a harmful drug that leads to dependency
not as a safe alternative to the other chemicals that are
more readily viewed as harmful and addictive.
By employing an integrated treatment approach that
is steeped in 12-Step tradition and philosophy,
Caron encourages productive changes via insight,
behavioral transition, spiritual growth, and family
involvement in treatment, as well as throughout the
recovery process. We do so in a nurturing way that
parallels the tranquil theme of our geography,
allowing the marijuana addict to achieve and maintain
a level of harmony that so often seems linked to the
rationale for the drug’s use in the first place.
19
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22
23
Galen Hall Road
P.O. Box 150
Wernersville, PA 19565-0150
800.678.2332
www.caron.org