Marijuana Addiction Treatment

Marijuana is the most widely used illicit drug in the Western world and the third most commonly used recreational drug after alcohol and tobacco. According to the World Health Organization, it also is the illicit substance most widely cultivated, trafficked, and used.

Although the long-term clinical outcome of marijuana use disorder may be less severe than other commonly used substances, it is by no means a “safe” drug. Sustained marijuana use can have negative impacts on the brain as well as the body. Studies have indicated a link between regular marijuana use and schizophrenia as well as a demonstrated relationship between marijuana use and a higher incidence of lung cancer.

Although there are no pharmacological treatments available with a proven impact on marijuana use disorder, there are several types of behavior therapy that may be effective in treating this disorder.

What is Marijuana?

Marijuana is an illicit psychoactive sedative drug from the cannabis (hemp) plant. The name marijuana is thought to have its origins in the Portuguese word mariguango, which translates as intoxicant. Marijuana consists of the dried and crushed leaves from the cannabis plant, which are typically smoked, but can also be eaten in baked goods or consumed as tea. In the United States, marijuana is typically smoked in rolled cigarettes (“joints”), in pipes or water pipes, or in hollowed-out cigars (“blunts”).

Marijuana is known by many names including pot, reefer, grass, weed, and many others. People’s experiences with marijuana can differ considerably depending on the potency of the drug. Many users experience sedative effects such as relaxation and drowsiness.

The psychoactive chemical in marijuana is delta-9-tetrahydrocannabinol (delta-9-THC or THC). THC is also the active ingredient in several FDA approved medications such as dranabinol and nabilone. These medications are used to treat medical conditions including glaucoma, severe nausea, vomiting, weight loss, and pain.

The Marijuana Plant The cannabis (hemp) plant, Cannabis sativa, is the source of marijuana and hashish. The cannabis plant contains more than 400 chemicals. At least 60 of the chemicals are cannabinoids (as they bind to cannabinoid receptors in the brain), but the most important of these cannabinoids is delta-9-tetrahydrocannabinol (THC). Delta-9- tetrahydrocannabinol is the plant’s main psychoactive chemical, although researchers are examining some of the other chemicals found in this plant for potential additional medicinal use. Various marijuana plants can significantly differ in how much THC is contained in each. Marijuana can contain 1% to 3% THC all the way up to 25%.


The absorption of THC depends primarily on the mode of consumption. The most rapid and efficient absorption of marijuana occurs through smoking. Inhalation results in absorption directly through the lungs, and the onset of the THC action begins within minutes. Assessments of blood plasma reveal that peak concentrations occur 30 to 60 minutes later. The drug effects can be experienced for two to four hours.

Oral ingestion of marijuana is much slower and relatively inefficient. The onset of action is longer than when smoked, taking as long as an hour. The marijuana is absorbed primarily through the gastrointestinal tract, and peak plasma levels can be delayed for as long as two to three hours following ingestion.

An important difference from absorption through smoking is that blood containing orally ingested marijuana goes through the liver before going to the brain. The liver processes or clears much of the THC so that lesser amounts have the opportunity to exert action in the brain; however, the drug effects following oral ingestion can be experienced for longer periods of time, generally four to six hours. The dose needed to create a comparable high when orally ingested is estimated as three times greater than that needed when smoking.

Cannabis Intoxication

Cannabis intoxication, a cannabis-related disorder coded as 292.89, is defined by DSM-5, as the following:

  • Recent use of cannabis
  • Clinically significant problematic behavioral or psychological changes (i.e., impaired motor coordination, euphoria, anxiety, sensation of slowed time, impaired judgment, social withdrawal) that developed during, or shortly after, cannabis use
  • At least 2 of the following signs, developing within 2 hours of cannabis use:
  • Conjunctival injection
  • Increased appetite
  • Dry mouth
  • Tachycardia

Respiratory Effects of Marijuana

The impact of chronic marijuana smoking on respiratory health has many similarities to that of tobacco smoking. Compared with nonsmokers, chronic marijuana smokers show increased likelihood of outpatient visits due to respiratory illness and exhibit respiratory symptoms of bronchitis at comparable rates to tobacco smokers. Chronic bronchitis can be moderately debilitating and increases the risk of additional infections.

As THC appears to suppress immune system function, recurrent bronchitis may further increase the risk of opportunistic respiratory infections such as pneumonia and aspergillosis. This is of concern particularly for those individuals with already compromised immune functions such as cancer and AIDS patients.

Airway obstruction and symptoms of chronic cough, sputum production, shortness of breath, and wheezing characterize chronic bronchitis. These symptoms are the result of airway inflammation and tissue damage caused by marijuana smoke that results in increased fluid production, cellular abnormalities, and reduced alveolar permeability. This damage begins long before overt symptoms such as cough or wheezing are evident. Cellular abnormalities include reductions in ciliating surface cells of the lungs that function to clear fluid from the lungs to the mouth and throat. As a result, marijuana smokers have substantially higher bronchitis index scores than nonsmokers, and comparable scores to tobacco smokers, even at young ages with only short histories of marijuana use. Investigations of chronic obstructive pulmonary disease (COPD) in chronic marijuana smokers have been inconclusive.

A common severe consequence of tobacco smoking, COPD includes chronic obstructive bronchitis or emphysema, and is characterized by impairment in small airway function rather than large airways.

Marijuana smokers exhibit almost identical degrees of histopathologic and molecular abnormalities associated with progression to COPD in tobacco smokers and several case reports have been identified. However, two earlier large-scale studies of COPD in chronic marijuana users have been inconclusive.

Chronic cannabis smoking is likely associated with respiratory cancer, although this link is not definitive. Cannabis smoking is clearly associated with similar processes and patterns of disease that lead to aerodigestive cancers among tobacco smokers. As noted previously, marijuana smoke contains more carcinogens than cigarette smoke. Marijuana interferes with normal cell function, including synthesis and functions of DNA and RNA, and appears to activate an enzyme that converts inactive carcinogens found in marijuana smoke into active carcinogens. Chronic marijuana smokers also show substantial cellular mutation associated with tumor progression.

Marijuana also reduces the ability of pulmonary alveolar macrophages to kill pathogens, including tumor cells, allowing tumors to grow more rapidly. Clinical reports of aerodigestive cancers in individuals who had a history of marijuana smoking with limited or no tobacco exposure have provided suggestive evidence of a link between marijuana use and cancer.

In addition, Zhang, et al., (1999) found increased risk for squamous-cell carcinoma of the head and neck for marijuana smokers compared with nonsmokers when tobacco smoking was statistically controlled. Similarly in a case-controlled hospital study in Casablanca, Morocco, Sasco, et al., (2002) found that the use of hashish was independently predictive of lung cancer.

The only epidemiological study that directly examined the risk of aerodigestive cancer in marijuana users reported no significant risk associated with cannabis. This study, however, included a relatively young cohort comprised of primarily experimental and light marijuana users rather than chronic heavy users.

Individuals who began smoking marijuana in the late 1960s are now approaching ages that are more likely to be associated with aerodigestive cancer; hence, future epidemiological studies should clarify better the risk of cancer associated with chronic cannabis use. Smoking both cannabis and tobacco warrants mention as this combination most likely produces an additive adverse effect on the respiratory system.

Tobacco smoking is common among cannabis users, as almost half of daily marijuana users also smoke tobacco. This subgroup of marijuana smokers merits careful study as they may be at particularly high risk for respiratory disease.

Cannabis derives from the cannabis sativa plant, a variety of hemp that
has been cultivated for much of human history. The leaves can be smoked,
though the flowering tops and buds are more potent; a resin from the plant
can also be concentrated into hash or hash oil. The main psychoactive
component is delta-9-tetrahydrocannabinol (THC), which is one of many
cannabinoids in the plant.
THC activates cannabinoid receptors in the brain. Two subtypes have
been identified: Type 1 is predominant in the brain and is responsible for
most of cannabis’ psychoactive properties; type 2 is in the periphery, especially
in white blood cells, and has effects on the immune system. There
are also some endogenous cannabinoids (called endocannabinoids), such
as anandamide, which is named after the Sanskrit word “ananda,” meaning
bliss. It’s not clear why we have this endocannabinoid system, but it is ubiquitous
throughout the central nervous system and appears to be part of the
normal regulation of various functions, including memory, pain sensation,
mood, and appetite (Ligresti et al, 2016).
Immediate effects
Cannabis’ immediate effects are euphoria, distortion of one’s sense of time,
and a feeling of enhanced perception of things like colors and music. Some
people experience hallucinations and anxiety, and drowsiness is common.
The ability to form new memories is impaired during intoxication, though
the ability to recall old memories is not affected. Immediate physiological
effects include peripheral vasodilation (responsible for users’ bloodshot
eyes, which is caused by swelling of blood vessels in the sclera, or conjunctival
injection) and elevated heart rate (to some degree, this is also caused
by peripheral vasodilation).
Overdoses lead to panic attacks, psychotic symptoms, palpitations and
tachycardia, and occasionally shortness of breath and chest pain.
Long-term effects
Chronic cannabis syndrome, formerly known as amotivational syndrome,
results from long-term regular use of cannabis—especially use during
adolescence, which is a vulnerable time for the developing brain. When the
immature endocannabinoid system is repeatedly exposed to THC, there
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can be long-term subtle effects on learning and adaptation. This may be
caused by interference with the normal process of neural pruning during
adolescence (Lubman et al, 2015).
Chronic cannabis syndrome has two components: reduction in the ability
to process and remember new information and skills, and lessened motivation
for achievement in general. This can hinder educational and career
trajectories, causing a user’s IQ to not meet that of age-matched peers.
In addition to these long-term cognitive effects, cannabis can worsen
a range of mental psychiatric symptoms. These include anxiety, with an
increased frequency and intensity of panic attacks, as well as depression.
Most alarmingly, there is an association between early cannabis use and
development of schizophrenia and other psychotic disorders. The risk for
psychosis increases with younger age of initiation and a family history of
any psychotic disorder or major mental health disorder. A recent review
estimated that chronic cannabis use is associated with a twofold increase in
risk of developing schizophrenia; however, the causal link is not established
(Gage et al, 2016).
Physical effects
Lungs. Inhaling smoke from any source exposes the lungs to potentially
toxic material, such as particulate matter or carcinogens. It can worsen
asthma and potentially cause chronic obstructive pulmonary disease.
Unlike tobacco cigarettes, cannabis joints do not have filters, allowing
more contaminants to enter the lungs. On the other hand, people generally
FUN FACT: An Anti-Munchies Drug
It’s well known that cannabis causes increased appetite,
otherwise known as the munchies. Pharmaceutical
companies have taken advantage of this property. For example,
the synthetic THC agent dronabinol (Marinol) is FDA-approved for
appetite restoration in AIDS wasting syndrome. Scientists have also
developed cannabinoid receptor antagonists as potential weight
loss agents, and in 2006, Sanofi Aventis launched a specific CB-1
antagonist called rimonabant (brand name Acomplia) (Pi-Sunyer
et al, 2006). Acomplia was first sold in Great Britain, with plans for
eventual FDA approval, but reports of depression and suicide as
apparent side effects caused it to be withdrawn from all markets.
smoke fewer joints than tobacco cigarettes, somewhat mitigating this
Heart. Regardless of how it is ingested, cannabis can raise the risk of heart
attacks in people with preexisting ischemic heart disease. The mechanism
for this risk is cannabis-induced tachycardia, which raises myocardial oxygen
demand. This risk is greatest within the first 20 minutes of starting use.
Immune system. Regular cannabis use can reduce immune function, which
is most problematic in those who are immunosuppressed, such as people
with HIV. Patients who use cannabis during or immediately after receiving
chemotherapy for cancer are at risk. Not only can cannabis further
reduce immune function, but processing of cannabis is not regulated by
the FDA—unlike dronabinol, which is FDA-approved for nausea due to
chemotherapy—so cannabis products may contain fungi (especially Aspergillis)
and other microorganisms that can lead to opportunistic infections
during periods of immunosuppression.
Fertility. Cannabis can reduce fertility in both men and women. It lowers
sperm counts in men, and long-term or heavy use can lead to irregular
menstrual cycles in women.
Cannabis withdrawal syndrome is well established and is more psychological
than physiological. Symptoms include depression, irritability, appetite
suppression, and headaches. In heavy users, there may be diarrhea and
other intestinal discomfort, including nausea and vomiting. Cannabis withdrawal
symptoms may last 3–7 days, depending on the amount of prior use.
As cannabis has become legal in many parts of the country, the cannabis
industry has grown and the products available have multiplied. As a practitioner,
you should be familiar with the major types of products, because
they vary significantly in potency, duration of action, and safety. Here is a
quick primer of the current state of cannabis products (see Table 10-1 for
a quick reference).
Smoked products. The most common and familiar form of cannabis products
are smokable joints or blunts, although water pipes and vaporizers are
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also used. In the 1960s and 1970s, the THC content in cultivated cannabis
plants was in the low single digits. However, newer strains have THC levels
in the 10%–20% range. There are also other varieties called “skunk,” which
are much more potent.
Hash oils. These are typically ingested using electronic vapor delivery
devices, essentially identical to e-cigarettes (see Chapter 9 for details).
The devices and hash oil e-liquids are sold legally in certain states. Many
e-cigarettes with refillable e-liquid tanks can also be used to vape hash oil,
making it potentially difficult to determine whether someone is vaping
nicotine or cannabis.
Edibles.In addition to the familiar pot brownies, now there are cannabis-containing
cookies and cupcakes, as well as hash oil–infused chocolate candy
TABLE 10-1. Available Cannabis Products
Product Description Notes
Smoked products
(aka joint)
Cannabis flowers, leaves, and/
or buds rolled in thin paper
and smoked like a tobacco
Simplest and most common
way to use cannabis
Blunt Cannabis rolled with tobacco
in a cigar
Skunk Cannabis plant bred with
higher THC concentration
British slang term
Water pipe (aka
bong or hookah)
Device to filter smoke through
water during the smoking
Paraphernalia for smoking;
illegal in some states
Vaporizer Type of device that uses a
battery to heat and vaporize
cannabis for inhalation
Paraphernalia for smoking;
illegal in some states (an
e-cigarette is a small,
portable vaporizer)
Hash oil Cannabis plant matter soaked
in a chemical solvent to extract
concentrated THC resin
Can be smoked, vaped, or
ingested orally
Edibles Wide variety of food products
infused with hash oil and
consumed orally
Baked goods and candies;
may have 5 mg–100 mg of
THC per product
Shatter (aka
butane honey oil,
dab, or wax)
THC resin extracted from
cannabis plant with butane as
the solvent
Flammable; may explode
during manufacturing or
bars, gummy bears, and lollipops. Users can even add raw cannabis plant
material to butter at home and simmer it to make cannabis-infused butter,
also known as “cannabutter.” In states where they are legal, cannabis-infused
products must carry a label disclosing the amount of cannabis they contain.
Compared to smoked cannabis, edibles have slower onset of action and
longer duration. Whereas smoked cannabis takes effect immediately and
lasts about 3 hours, edibles have a delayed onset of an hour or so, and can
last 8 hours or more. Portion control is difficult, and in some cases dangerous,
particularly when there are children around. A cannabis chocolate bar,
for example, may be one dose per square, but someone who mistakenly eats
the entire bar would experience paranoia, hallucinations, and problems
with coordination.
Synthetic cannabinoids. These versions of cannabis were originally developed
at university and drug company labs, initially for research into
developing medications. Eventually, these compounds were coopted by
clandestine chemists to create designer drugs such as spice, K2, and kush,
all of which are much more powerful than natural cannabis. There is more
information on these substances in Chapter 13.
Cannabis users often do not have insight about how the drug has affected
their lives. A common issue in young users is poor performance at school
or jobs. I’ll ask something like, “Two years ago, where did you see yourself
in terms of what you would achieve?” They might say, “I would have had a
ODD FACT: Cannabis
Hyperemesis Syndrome
Few people have heard of an unusual syndrome that
sometimes occurs with heavy cannabis use: Patients will experience
severe nausea and vomiting. This is particularly strange
because one of THC’s therapeutic effects is reducing nausea, rather
than triggering it. Cessation of cannabis use will stop the nausea,
and long hot baths and showers provide significant relief, which is
a clinical clue to diagnosis of this rare syndrome. With more widespread
use of cannabis products as more U.S. states legalize their
possession, cannabis hyperemesis may become more common.
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job or gone to college.” Then we discuss how things got delayed, and I’ll ask,
“Why did your life go off track? What were you doing instead?” Cannabis
is often the explanation, and we engage in that discussion.
In terms of school, cannabis can impair progress in two interconnected
ways: It decreases the motivation to study, but it also decreases users’ comprehension
and memory of what they are studying. Some will attribute
their lack of attention in class to not liking the course, or they might say
they were spending time doing other things besides studying. I point out
one of the things they were doing was using marijuana.
It can be difficult to know how much THC patients are consuming
because there are so many strains. One way to get a rough idea is to ask how
much they are spending on their habit per day or per week. For example, a
“dime bag” refers to a $10 bag, and a “quarter” is a $25 bag. The amount of
cannabis in these bags varies, but commonly a dime bag will contain about
1 gram, which might be enough for a couple of joints.
Ask about psychiatric symptoms, especially anxiety and hallucinations.
Hallucinatory experiences are more common among older users and with
large amounts of cannabis. If a patient has an established anxiety disorder,
look for the relationship between cannabis use and those symptoms.
CASE REVISITED: J smokes 6 to 10 joints most days. His use has escalated,
and he has been through several cycles of withdrawal, with symptoms
of nausea, anxiety, and irritability. He craves cannabis, restricts his
relationships to regular cannabis users, has driven under the influence, and
was once arrested for possession. I diagnose him with severe cannabis use
disorder, as well as substance-induced anxiety disorder.
Since there is no pharmacotherapy helpful in reducing cannabis use, treatment
involves a combination of motivational interviewing, help with detox,
and behavioral strategies.
Motivational interviewing: Discussing pros
and cons of cannabis with your patients
Cannabis is unique among substances of abuse in that its legal status is
in flux, and the legalization movement has provided users with various
rationales to defend their use. Regardless of whether you believe cannabis
has benefits, you should be ready to have informed discussions with your
patients about the issue. Here are some typical statements regarding cannabis
use that you may hear from your patients, followed by my take on these
issues and how I usually discuss them with patients.
“I use marijuana as medical treatment.” As of this writing, medical marijuana
is legal in 28 states. How is medical marijuana different from dronabinol,
which has long been legal to prescribe throughout the U.S.? Dronabinol
is a highly regulated compound that is purified THC. Medical marijuana,
by contrast, refers to a wide range of products, most of which have little
regulation or quality control, although this situation may improve as states
implement medical marijuana legislation.
There is evidence for cannabis’ effectiveness in a small number of conditions,
including intractable nausea from cancer chemotherapy and appetite
enhancement for AIDS wasting syndrome, the two indications for which
dronabinol has FDA approval. It is also used off-label for pain management,
muscle spasms, glaucoma, and multiple sclerosis. However, even for these
conditions, cannabis is considered at best second-line treatment.
Scientific evidence does not support efficacy of cannabis for psychiatric
illnesses. In practice, when patients are using cannabis, it is more difficult
to gauge whether the medication you are prescribing (such as an antidepressant
or benzodiazepine) is having a therapeutic effect.
“Many successful people get high.” Presidents, CEOs, journalists, movie
stars—it’s not hard to identify prominent and successful people who have
used cannabis. Some patients believe this means there is no harm in using
it. But for all the success stories, there are many famous people (Lindsay
Lohan, Willie Nelson, Macaulay Culkin) who have ongoing and public
problems caused by their addiction. Many celebrities have a good deal of
money and a team of high-powered lawyers to help them avoid jail or large
fines. Your patients probably don’t.
“I’m not addicted; I’m using it recreationally.” Some patients describe their cannabis
use as casual and recreational, which may be true, but if they are seeking
psychiatric treatment, you should be skeptical of how benign that use really
is. In these cases, I’ll use my standard motivational interviewing techniques
to explore whether patients are, in fact, ambivalent about their use. I’ll
ask, “What are the good things you are using cannabis for? What are the
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less-good things? Do you see yourself continuing to use cannabis in 1 year?
5 years? 5 years ago, did you see yourself in the situation you are in now?”
These questions help to develop patients’ sense of discrepancy between what
they want for themselves and what their cannabis use has led to.
“I quit using cocaine, which was a much worse drug for me, but I don’t want to
give up marijuana.” Patients who are in recovery—especially early recovery—from
another substance use disorder may not want to give up using
cannabis. They may see it as less problematic because the consequences of
their use of other illicit drugs like heroin or cocaine were much more prominent.
However, I remind them that cannabis is a mind-altering chemical
that can alter their judgment and impair their ability to make good decisions.
Continuing to use cannabis can lead patients back down the slippery
slope of using other drugs, undoing their progress toward recovery. I tell
patients that it is often easier to say no to all drug use than to determine
how much drug use is too much.
Cannabis detox
Withdrawal symptoms are generally mild, but can be severe in very heavy
and chronic users, with symptoms like nausea and vomiting, headache,
anxiety, insomnia, and irritability. Marijuana detox is usually done in the
outpatient setting, and is supportive. I tell patients that the first 5–7 days
of withdrawal will be difficult, so they should not schedule any activities
during that time and should concentrate on getting plenty of rest and fluids.
I will sometimes prescribe an antiemetic, such as Phenergan (promethazine)
or Compazine (prochlorperazine), and acetaminophen or ibuprofen
for headaches.
There are no approved medications for treating cannabis use disorder.
However, some people have tried dronabinol (Marinol) as substitution
treatment for cannabis abuse. One clinical trial showed that it did not
improve abstinence rates (Levin et al, 2011). In part, this appears to be
because people who smoke are used to an immediate onset, whereas
dronabinol is administered orally and its onset is delayed.
Antidepressants are helpful for longer-term depression or anxiety after
immediate withdrawal. Any of the SSRIs or SNRIs are reasonable in my
experience. I avoid benzodiazepines due to the potential for misuse, especially
in someone who has already established a substance use disorder.
Behavioral treatment
Behavioral treatment is the mainstay of treatment for cannabis use disorder.
Some patients will want to reduce their use to a controlled level instead of
quitting completely; I remind them that it can be hard to determine what a
safe level of use really is. If a patient is reluctant to cut down or quit, I will
say, “Let’s do a trial of abstinence,” or, “Let’s try cutting down your use for
a specified period.” I usually recommend a trial of abstinence for at least 1
month, ideally 3 months. I justify this to the patient by saying, “This will
help us determine whether cannabis may actually be doing something
beneficial.” Often the patient will see an improvement in other issues with
a reduction of cannabis use, which helps make the case to extend the trial.
Typical referral resources include 12-step self-help groups such as
Narcotics Anonymous (NA), individual counseling with a therapist, or
residential treatment if warranted by the patient’s environment or severity
of use. NA groups have many members who have used cannabis regularly,
even if that is not their drug of choice, so patients with a primary cannabis
use disorder who have not used other illicit substances can still find meaning
in attending these meetings. They will also be able to find a sponsor
who has experience and familiarity with the challenges they are facing.
Occasionally, patients will attend an NA meeting where members do not
regard cannabis as a drug of abuse. I always ask patients what they thought
of their meetings, and if I hear something concerning, I will help the patient
process it or recommend changing to a different meeting.
Individual therapy can help address maladaptive coping skills, or develop
coping skills a patient might lack due to early age of onset of cannabis use.

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