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Assessment and management of cannabis use disorders in primary care

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800 BMJ | 10 APRIL 2010 | VOLUME 340
CLINICAL REVIEW
For the full versions of these articles see bmj.com
Assessment and management of
cannabis use disorders in primary care
Adam R Winstock,1 Chris Ford,2 3 John Witton1
1National Addiction Centre, Institute
of Psychiatry, King’s College
London, London SE5 8AF
2Substance Misuse Management
in General Practice (SMMGP),
c/o NTA, Skipton House, London
SE1 6LH
324 Lonsdale Road, London NW6 6SY
Correspondence to: A R Winstock
Adam.winstock@kcl.ac.uk
Cite this as: BMJ 2010;340:c1571
doi: 10.1136/bmj.c1571
About a third of adults in the UK have tried cannabis, and 2.5
million people, mostly 16-29 year olds, have used it in the
past year.1 Although most people who smoke cannabis will
develop neither severe mental health problems nor depend-
ence, regular use of cannabis may be associated with a range
of health, emotional, behavioural, social, and legal prob-
lems, particularly in young, pregnant, and severely mentally
ill people.2 3 The past decade has seen a shift in available
cannabis preparations from resinous “hash” to intensively
grown high potency herbal preparations, often referred to
as skunk, which now dominates the UK market.
4
Compared
with traditional cannabis preparations, skunk tends to have
higher levels of tetrahydrocannabinol, the main psychoac-
tive constituent of cannabis, and lower levels of the anxi-
olytic cannabinoid cannabidiol. In January 2009 cannabis
was returned to its original class B classification (from class
C) under the UK Misuse of Drugs Act.
Despite high levels of use, only 6% of those seeking treat-
ment for substance misuse in England cite cannabis as their
major drug of concern, and most of those with cannabis use
disorders do not have cannabis use as their presenting com-
plaint (box 1).
5
Low levels of treatment seeking may reflect a
lack of awareness of the associated harms of cannabis.
w1
This
review highlights the adverse health outcomes associated
with cannabis and outlines optimal approaches to assessing
and managing cannabis use in primary care.
Methods
We searched electronic databases, including Medline and
PsycINFO; the Cochrane Library; specialist websites; data-
bases of England’s National Treatment Agency for Substance
Misuse and of the UK centre DrugScope; the US National
Institute on Drug Abuse; the European Monitoring Centre
for Drugs and Drug Addiction; and Australia’s National
Cannabis Prevention and Information Centre. We also con-
sulted primary care providers and specialists in addiction
treatment.
How does cannabis exert its effect?
Metabolites of cannabis act on the body’s endogenous
cannabinoid system via type 1 cannabinoid receptors (CB1
receptors) in the central nervous system and CB
2
receptors
peripherally. They may modulate mood, memory, cognition,
sleep, and appetite.w2
What are the effects of intoxication?
Most people smoke cannabis for its relaxant and euphoriant
eects (box 2). The impact of higher potency cannabis will
depend partly on its ratio of tetrahydrocannabinol to can-
nabidiol and whether users are able and willing to titrate
their consumption as they might alcohol.3 6 The authors
of a recent review suggested that more potent forms may
increase the risk of dependence and adverse psychological
experiences.3
SUMMARY POINTS
Cannabis use is common, especially among young people
The greatest risk of harm from cannabis use is in young
people and those who are pregnant or have serious mental
illness
A tenth of cannabis users develop dependence, with three
quarters of them experiencing withdrawal symptoms on
cessation
Most dependent users have concurrent dependence on
tobacco, which increases the health risks and worsens
outcomes for cannabis treatment
Brief interventions and advice on harm reduction can
improve outcomes
Psychoeducation (for a better understanding of
dependence), sleep hygiene, nicotine replacement therapy
(where indicated), and brief symptomatic relief form the
mainstay of withdrawal management
Dependent users may present with symptoms suggestive
of depression, but diagnosis and treatment should
be deferred until two to four weeks after withdrawal to
improve diagnostic accuracy
Box 1 | What problems might cannabis users present
with in primary care?
Respiratory problems, such as exacerbation of asthma, •
chronic obstructive airways disease, wheeze or
prolonged cough, or other chest symptoms
Mental health symptoms, such as anxiety, depression, •
paranoia, panic, depersonalisation, exacerbation of an
underlying mental health condition
Problems with concentration while studying or with •
employment and relationships
Difficulties stopping cannabis use•
Legal or employment problems (arising from use of •
cannabis)
bmj.com Ж
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author Chris Ford, at
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BMJ | 10 APRIL 2010 | VOLUME 340 801
CLINICAL REVIEW
Routes of use
Cannabis is often rolled in a cigarette paper and smoked
with tobacco in a “joint” or “spli,” and it produces inhaled
carcinogens. Most carcinogens in tobacco are present in
cannabis. Typical cannabis use results in a larger volume of
smoke being inhaled than with ordinary tobacco products
and a fivefold increase in concentrations of carboxyhaema-
globin.7 Tetrahydrocannabinol is fat soluble and is absorbed
from the gastrointestinal tract. Although oral ingestion of
cannabis avoids the risks associated with smoking, sec-
ondary active metabolites are formed and dose titration is
dicult.w3 Oral use may lead to intense, unpredictable pro-
longed intoxication.w4
Harms and risks associated with the use of cannabis
Table 1 outlines the harms and risks associated with can-
nabis use, such as acute and chronic eects and possible
risks in specific populations.
Associations with use at young age
Large population based longitudinal studies have shown that
the earlier the age of first use of cannabis, the greater the risk
of dependence, other problems of substance misuse, mental
health problems, and poor emotional, academic, and social
development.3 w5 Vulnerability to the reinforcing positive
eects of cannabis use and to dependence, has a heritable
component.w6
Pulmonary harms
Cannabis smoking shows a dose-response relation with pul-
monary risk in the same way that tobacco smoking does. A
longitudinal study of young cannabis smokers showed that
regular heavy use can produce chronic inflammatory changes
in the respiratory tract, resulting in increased symptoms of
chronic bronchitis such as coughing, shortness of breath, pro-
duction of sputum, and wheezing.
8
A study comparing results
of pulmonary function tests and computed tomography scans
across dierent smoking groups estimated that one cannabis
joint caused the equivalent airflow obstruction associated
with smoking two and a half to five cigarettes.9 A recent cross
sectional study examining an older population of smokers
suggests that concurrent smoking of cannabis and tobacco
leads to synergistic respiratory harm, whereas smoking can-
nabis alone probably does not lead to chronic obstructive
pulmonary disease.10 However, a large case-control study
from New Zealand does suggest that cannabis smoking is an
independent risk factor for lung malignancy; heavy smokers
(more than 10 years of smoking cannabis joints) had a relative
risk of 5.7 after adjustment for age, tobacco use, and family
history of lung cancer.11 A large prospective study found that
cannabis use may be a risk for coronary events, especially in
those with pre-existing cardiovascular disease.w8
Mental health and cognition
Observational evidence associates cannabis use and psy-
chotic disorders, but causality is not established.w9 Cannabis
use is associated with double the risk of schizophrenia (from
0.7 in 1000 to 1.4 in 1000), and some evidence exists that
starting use under the age of 16 years increases the risk.
12
A
cross sectional study showed that a family history of psychotic
illness and a personal history of unusual experiences raised
the risk of psychotic illness associated with cannabis use.13
A recent review highlighted consistent evidence that onset
Box 2 | Physiological and psychological effects of cannabis*
Psychological (mood/perceptual) effects
A sense of euphoria and relaxation•
Perceptual distortions, time distortion, and the •
intensification of sensory experiences
Impairment of attention, concentration, short term •
memory, information processing, and reaction time
Feelings of greater emotional and physical sensitivity•
Anxiety, panic, and paranoia•
Physiological effects
Increase in appetite•
Increase in heart rate, decrease in blood pressure•
Conjunctival injection and suffusion•
Dry mouth•
Impaired psychomotor coordination and sedation•
*The effects peak after 30 minutes and last for two to four hours
Table 1
|
Harms and risks associated with cannabis use. Adapted from the 2009 guidelines from Australia’s National Cannabis
Prevention and Information Centrew7 and from Hall and Degenhardt3
Acute intoxication risks Impaired attention, memory, and psychomotor performance while intoxicated
Increased risk of road traffic crashes, especially if cannabis is mixed with alcohol
Psychotic symptoms at high doses
Most probable chronic
effects
Dependence (1 in 10 users)
Subtle cognitive impairment in attention, verbal memory, and the organisation and integration of complex information in
daily user (with >10 years’ use). Some evidence of reversibility with prolonged abstinence
Pulmonary disease and respiratory symptoms such as chronic obstructive pulmonary disease and chronic cough
(synergistic harm with tobacco)
Malignancy of the oropharynx
Possible chronic effects Xerostomia (dry mouth) and consequent dental health problems
Some evidence that cannabis may affect female fertility
In utero exposure to cannabis may lead to low birthweight babies and later behavioural, problem solving, and attention
difficulties
Increased rate of lung cancer
Probable risks in specific
populations
Impaired personal and educational attainment
Adolescent cannabis use is associated with: higher rates of truancy, delinquency, and criminality; higher rates of problems
of other substance misuse, including alcohol; poorer academic achievement and educational attainment, with more
unemployment; lower levels of relationship satisfaction; possible exacerbation of mental health conditions such as
depression, anxiety, and psychotic conditions
Limited or no evidence Birth defects (except low birth weight, for which good evidence exists)
802 BMJ | 10 APRIL 2010 | VOLUME 340
CLINICAL REVIEW
of schizophrenia presents earlier (by 1.9-6.7 years) in male
cannabis smokers.
14
A recent systematic review found that
cannabis use was associated with increased relapse and non-
adherence to medication in patients with schizophrenia.15
Cross sectional and cohort studies have found higher
levels of depressive symptoms in cannabis users than in
non-users.
w10
However, a systematic review concluded that
cannabis use does not cause aective disorders.12 Rates of
cannabis use are higher in those with anxiety disorders than
in those without, and heavy users of cannabis have higher
levels of anxiety, but the nature of this relation is not clear.16
Differentiating between chronic cannabis intoxication
and psychiatric disorders
The presenting symptoms of chronic cannabis use and
intoxication can sometimes be confused with those of
depression (lethargy, sleep and appetite disturbance, social
withdrawal, problems at work or at home, cognitive impair-
ment). Symptoms may improve or resolve outside periods
of intoxication or withdrawal. Psychiatric disorders that are
unrelated to cannabis use may have been present before
the onset of use and their symptoms are likely to persist
with abstinence from cannabis. If symptoms resolve when
cannabis use ceases, the likelihood of a primary psychiat-
ric diagnosis diminishes. In a small inpatient withdrawal
study of 20 heavy users of cannabis, mean baseline depres-
sion symptom scores reduced to normal levels after four
weeks of abstinence.
17
The diagnosis of a depressive dis-
order and start of antidepressants should therefore usually
be deferred until after a period or two to four weeks of absti-
nence. Resolution of aective symptoms after cessation
may act as a good motivator for maintaining abstinence
(see the full version of this article on bmj.com for figure
1, a decision pathway for assessing aective symptoms in
cannabis users).
Recent imaging studies have identified reductions in the
volumes of the amygdala and hippocampus that are related
to cannabis use,18 consistent with studies that have identi-
fied duration of use and dose related impairments in mem-
ory and attention in long term heavy users of cannabis.19
Identifying the cannabis user for whom use is a problem
Although problems of cannabis use can arise at any level of
use, however low, cannabis use disorders and other problems
are more likely to arise in long term, heavy daily users than in
casual, infrequent users. Screening questions about cannabis
use and other substance use can accompany other lifestyle
questions about tobacco and alcohol use and can be raised
during consultations on smoking, mental health, and sleep
disturbances (fig 2). Some patients may try to avoid such
questions or they may ask subtle questions to check that drug
use is OK to talk about. Others will be relieved to be asked.
Questions should focus on frequency of use and amount
used. If a patient’s cannabis use is not impairing any aspect
of psychosocial functioning, and he or she seems to control
the use and recognise the risks and when use might be con-
sidered a problem, then the intervention can be restricted to
giving health information and discussing risks.
Box 3 lists questions that may be useful in quantifying
the level of use and confirming the presence of a cannabis
use disorder. Both ICD-10 (the international classification
of diseases, 10th revision) and the DSM-IV-TR (Diagnostic
and Statistical Manual of Mental Disorders, fourth edition,
text revision) recognise cannabis as a substance that causes
dependence. About 1 in 10 users develops dependence.20
Dependence is defined by a cluster of symptoms, including
loss of control, inability to cut down or stop, preoccupation
with use, neglecting activities unrelated to use, continued
use despite experiencing problems related to use, and the
development of tolerance and withdrawal (which results
from the body requiring (but not receiving) more of the drug
to achieve the same eect).
What if assessment suggests problematic use or
dependency?
Although some dependent users recognise their use as
problematic, others may not, and in such cases a motiva-
tional approach may be appropriate: to raise awareness of
Box 3 | Questions to ask cannabis users to identify
problems, including withdrawal
How long does a gram (or an eighth of an ounce (3.5 g)) •
last you? How many joints a day do you smoke? How
many joints do you make from a gram?
On how many days a week or month do you smoke?•
Do you mix it with tobacco? Do you smoke cigarettes as •
well?
Does your cannabis use cause you any problems, such as •
anxiety, cough, interference with your sleep or appetite?
Does your smoking ever interfere with what you want to •
do or what you have to do, such as working or studying?
Have you ever thought about cutting down or stopping?•
Have you ever tried to cut down or stop? What happened? •
Were you able to sleep? Do you get irritable or moody?
If you managed to stop for a while, how did you feel •
afterwards?
Fig 2 I
Identifying and responding to cannabis use disorders
Regular weekly/daily use: screen for
dependent/problematic use with brief
intervention framework (e.g. FRAMES*)
Infrequent/non-problematic use: give
information on related health risks and highlight
tobacco related harms; give harm reduction advice
If yes, give advice on gradual dose reduction,
withdrawal symptoms, and sleep hygiene, and
on nicotine replacement therapy if appropriate
Cannabis use identified at interview
If withdrawal is a barrier to abstinence, consider brief periods of symptomatic relief
Is the patient motivated to stop/cut down?
Is there evidence of dependence?
If the patient successfully
reduces use:
Give positive feedback and
discuss simple relapse
prevention techniques
Provide follow-up
assessment of any baseline
psychological symptoms
* Feedback, Responsibility (of individual for change), Advice, Menu (of change options), Empathic
(counselling style), and enhancement (of Self efficacy)
If the patient cannot reduce
use, consider referral for
extended psychological
intervention (e.g. group
therapy, 1:1 cognitive
behavioural therapy,
motivational interview)
Give harm reduction advice
If no, conduct brief intervention and explain
dose related health risk and encourage
patient to consider what would prompt
them to think about cutting down/stopping
BMJ | 10 APRIL 2010 | VOLUME 340 803
CLINICAL REVIEW
the consequences of use, explore and resolve ambivalence,
and subsequently motivate change.
21
Asking the patient to
draw up a pros and cons table can be good way to get them
to think about their use (table 2). Although abstinence may
be an optimal outcome, a reduction in use may be a more
attainable initial goal.22
No intervention to date has proved consistently eective
for the majority of those with dependence on cannabis. Tri-
als in the United States and Australia support four methods
of behavioural based interventions: motivational interview-
ing, motivational enhancement therapy, cognitive behav-
ioural therapy, and contingency management.
Cognitive behavioural therapy and contingency manage-
ment have the most evidence for reduction in cannabis use
and maintaining abstinence.
22
For younger users, family
based interventions may be more eective.
22
Brief, behav-
iourally based interventions suitable for delivery by general
practitioners may be eective. One randomised study of a
brief motivational intervention in young users showed a
reduction in cannabis use from 15 days to five days a month,
and at three months one in six were abstinent.
23
Extended
abstinence can be supported through maintaining motiva-
tion and the use of relapse prevention techniques.22 A ran-
domised trial that enrolled members of the general public
who fulfilled criteria for dependency explored contingency
management (money vouchers for continued abstinence)
and motivational and cognitive behavioural therapy inter-
ventions for maintaining abstinence. Contingency manage-
ment alone led to the highest rates of initial abstinence in
adult cannabis smokers, but longer term abstinence was
helped by the use of coping skills and post-treatment self
ecacy training.24 A computer based intervention to treat
comorbid depression and cannabis dependence tested in
a randomised controlled trial seemed to have potential in
managing this group.w11
Figure 2 outlines in an algorithm how to identify and
respond to cannabis use disorders.
How to manage withdrawal
Symptoms of withdrawal (table 2) may be a barrier to absti-
nence as they may be of similar intensity to those accompany-
ing tobacco cessation. As many as 85% of users experience
withdrawal.
20
A cross sectional survey of treatment seekers
found that concurrent use of cannabis and tobacco makes
it harder to quit either substance
25
and withdrawal tends to
be more severe in cannabis users who are also heavy users
of tobacco and in cannabis users with mental illness. With-
drawal symptoms peak on day 2 or 3, and most are over by
day 7. Sleep problems and vivid dreams can continue for two
to three weeks.20
No evidence based pharmacological intervention exists
for managing cannabis withdrawal.26 Some small stud-
ies exploring the utility of oral tetrahydrocannabinol show
promise in reducing withdrawal and craving.27 If bupro-
pion is used in nicotine dependence it must begin at least
one week before cessation of both substances, as starting
treatment on day 1 of cannabis cessation may exacerbate
withdrawal symptoms.28 Our experience is that providing
a patient with information about withdrawal symptoms
may help them to prepare for discomfort, which if severe
can be alleviated with a few days of symptomatic relief.
Most dependent users, however, probably do not require
any drug intervention to manage their withdrawal. Box
4 outlines what advice to give to patients on managing
wit hdrawal.
Cessation of use can be monitored with urine tests over
several weeks for the inactive metabolite of cannabis
Table 2
|
Pros and cons of cannabis use—a decisional matrix
Good things Bad things
Continuing cannabis use Feeling relaxed; rolling a
joint; socialising with friends;
sleeping well
Cost; partner unhappy; need to stop going
out as much; health worries; smell of smoke
on clothes
Stopping/reducing cannabis use Save money; go out more; get
healthier; partner happy
Not being able to relax; not seeing some old
friends; not sleeping as well
Box 4 | Management of withdrawal
Advise gradual reduction in amount of cannabis used •
before cessation
Suggest that the patient delays first use of cannabis till •
later in the day
Suggest that the patient considers use of nicotine •
replacement therapy if he or she plans to stop separate
tobacco use at the same time
Advise the patient on good sleep hygiene, including •
avoidance of caffeine, which may exacerbate irritability,
restlessness, and insomnia
Suggest relaxation, progressive muscular relaxation, •
distraction
Suggest psychoeducation sessions for the user and •
family members on the nature, duration, and severity
of withdrawal, to help with a better understanding of
dependence and reduce likelihood of relapse
Advise the patient to avoid the cues and triggers •
associated with cannabis use
Prescribe short term analgesia and sedation for •
withdrawal symptoms if required
If irritability and restlessness are marked, consider •
prescribing very low dose diazepam for three to four days
ONGOING RESEARCH
A multicentre European trial is examining risk and •
protective factors and multidimensional family therapy
for adolescents
US trials are investigating effective interventions to •
manage withdrawal and to support abstinence in
otherwise healthy populations, including the use of
computerised treatments, contingency management
with adolescents, and cannabis patches
The UK MIDAS trial is examining whether an integrated •
intervention that combines motivational interviewing
and cognitive behavioural therapy can effectively reduce
use in those with severe mental illness
UNANSWERED QUESTIONS
What is the precise nature of the association between •
cannabis use and development of schizophrenia?
How do higher potency strains of cannabis affect the •
physical and psychological risks of individuals and the
population as a whole?
What is the degree of recovery in cognitive functioning •
with prolonged abstinence?
What is the neurobiological mechanism underlying •
cannabis withdrawal?
804 BMJ | 10 APRIL 2010 | VOLUME 340
CLINICAL REVIEW
( carboxy-tetrahydrocannabinol); heavy smokers may con-
tinue to be positive for cannabis for up to six weeks.w12
Harm minimisation for those who choose to continue
using cannabis
Initial assessment and feedback could focus on the
pulmonary harms of smoking, citing strategies that
target both tobacco and cannabis (for example, Health
Scotland’s publication Fags ‘n’ Hash29).
Water pipes (also known as bongs), which cool and fil-
ter smoke, are not a safer way of smoking. They filter out
more tetrahydrocannabinol than they do tar, resulting in
greater tar delivery to the lungs.w13 The role of vaporisers
(which heat the plant material, releasing the tetrahydro-
cannabinol as a vapour but avoiding combustion) as an
eective harm reduction intervention is uncertain.w13- w15
Box 5 (available on bmj.com) outlines advice for patients
on how they can reduce their risk of harm from cannabis
use.
When to refer to a specialist
Persistent use despite recognition of harms and unsuccessful
attempts to reduce use should lead to specialist referral; con-
sider specialist referral also for those with severe comorbid
mental health problems and those who are pregnant.
Contributors: ARW conceived the review, wrote the initial draft, prepared the final
draft, and is the guarantor; CF helped with conception of the review and wrote the
screening and assessment sections; JW helped with the literature search and the
preparation of the final draft for submission.
Competing interests: All authors have completed the Unified Competing
Interest form at www.icmje.org/coi_disclosure.pdf (available on request from
the corresponding author) and declare (1) no support from any company for the
submitted work; (2) no relationships with any companies that might have an
interest in the submitted work in the previous 3 years; (3) their spouses, partners,
or children have no financial relationships that may be relevant to the submitted
work; and (4) no non-financial interests that may be relevant to the submitted work.
Provenance and peer review: Not commissioned; externally peer reviewed.
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ADDITIONAL EDUCATIONAL RESOURCES
Know Cannabis (www.knowcannabis.org.uk)—Self help website•
Talk to Frank (www.talktofrank.com/section.aspx?ID=110)—Self help website, with helpline •
(phone/online)
Young Minds (youngminds.org.uk)—Self help website focusing on young people’s mental •
wellbeing
Marijuana Anonymous (www.marijuana-anonymous.org)—Online support group for users •
wishing to quit
Connexions (www.connexions.gov.uk)—Website for young people aged 13-19 years that offers •
support and links them with a practitioner or personal adviser
Helpfinder, DrugScope (www.drugscope.org.uk/resources/databases/helpfinder.htm)—•
DrugScope’s database of drug treatment services
TIPS FOR NON-SPECIALISTS
Most cannabis users will not develop dependence or severe mental health problems. Concerns •
should be highest for daily smokers, adolescents, those who are pregnant, and those with
coexisting severe mental illness
A gradual reduction in tolerance and levels of use among daily smokers can be helped by •
getting users to delay the time of first use in the day and to engage in other daytime activities
The insomnia, irritability, and craving that can occur for a few days on cessation of cannabis •
can be a barrier to attaining abstinence. Cessation is less likely to result in serious withdrawal
symptoms if use has fallen to lower levels before quit attempts
If users are reluctant to accept the possibility of a causal relation between cannabis use and •
an adverse psychological experience or state, encouraging a period of abstinence and self
monitoring using a diary and feedback from trusted friends or family members can be useful
Consider discussing concurrent tobacco dependence with patients even if they only use •
tobacco when they use cannabis
... Marijuana is the most widely used drug in many developed countries, and it is the illicit drug most commonly used by those who screen positive for drug use in primary care. 1 It is the third most common substance associated with dependence after alcohol and tobacco. 2 Admissions to treatment for marijuana use disorders are increasing in the United States, 3 as it is associated with physical consequences [4][5][6][7] and use at early ages is associated with mental health problems. 8 However, many marijuana users do not experience major health consequences, 1 which reduces the likelihood of treatment seeking or treatment engagement. ...
... This, and the absence of empirically supported intervention approaches for addressing marijuana use in primary care, represents important challenges for health care providers, in a moment when there are policy changes around marijuana use across the United States that may increase its use in the general population. 1 Screening and brief intervention have proven to be efficacious for unhealthy alcohol use. 9 Such a brief intervention typically involves feedback and discussion of negative consequences and risks that can enhance motivation to reduce intake as well as provision of nonjudgmental advice and negotiating a plan. ...
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Background: The use of brief intervention for decreasing frequent marijuana use holds potential, but its efficacy in primary care is not known. Methods: Objective: To assess the impact of two brief interventions on marijuana use among daily/ or almost daily marijuana users. Design: Subgroup analysis of a 3-arm randomized clinical trial of two brief counseling interventions compared to no brief intervention on daily marijuana use in a primary care setting (ASPIRE). Participants: ASPIRE study participants who both reported 21-30 days of marijuana use during the past month and identified marijuana as their drug of most concern. Interventions: 1) Brief Negotiated Interview (BNI), a 10-15 minute structured interview, and 2) an Adaptation of Motivational Interviewing (MOTIV), a 30-45 minute intervention. Control group participants received only a list of substance use treatment resources. Main measures: The primary outcome was number of days of marijuana use in the past 30 days at the 6-month follow-up. Secondary outcomes were 1) number of days of marijuana use at 6-week follow-up and 2) drug problems (Short Inventory of Problems, SIP-D) at 6-week and 6-month. Differences between intervention groups were analyzed using negative binomial regression models. Results: Among the 167 eligible participants, we did not find any significant impact of either of the two interventions on past 30 days of marijuana use at 6-months [adjusted incidence rate ratio (aIRR): 0.95 (95% confidence interval (CI)):0.75-1.15, p = 0.82 for BNI vs. control; aIRR:1.02, 95%CI:0.85-1.23, p = 0.82 for MOTIV vs. control]. There was no significant impact on drug-related problems at 6-month follow-up [aIRR:1.12 (95%CI:0.69-1.82) p = 0.66 and aIRR:1.46 (95%CI:0.89-2.38) p = 0.27 for BNI vs. control and MOTIV vs. control, respectively]. Results were similar at 6 weeks. Conclusions: Brief intervention has no apparent impact on marijuana use or drug-related problems among primary care patients with frequent marijuana use identified by screening.
... Les recommandations européennes sont vierges de conduite à tenir vis-à-vis de la prévention de ces effets, de leur dépistage et de leur prise en charge spécifique, sans aucune mention du cannabis [17][18][19]. Les recommandations américaines, elles, stipulent de prendre en compte une éventuelle intoxication cocaïnique avec une recommandation de testing urinaire de dépistage de drogues illicites en cas de SCA < 50 ans [20] ; les recommandations de prise en charge des complications liées au cannabis ne mentionnent par ailleurs pas les potentielles atteintes cardiovasculaires [21]. Non invasif, hors champs bioéthique : pas de consentement nécessaire *Non corrélé à l'imprégnation tissulaire **∆9-THC-COOH = cannabinol ***11OH-THC = acide nor11∆9-THC Cannabinoïdes de synthèse : analyse par chromatographie en phase gazeuse (GC) couplée à une spectrométrie à infrarouge (GC-IR) ou une spectroscopie à résonance magnétique nucléaire, sur prélèvements multiples (sérum, urines, cheveux). ...
... Cannabis use has been shown to impair cognitive functions from basic, such as motor coordination to more complex executive functions [172]. Chronic cannabis was associated with cognitive problems such as addiction, distorted perceptions, difficulty in thinking and problem solving, working memory deficits, and abnormal social behavior [152,[171][172][173][174][175]. These deficits vary in severity and depend on the quantity, recency, age of onset and duration of cannabis use. ...
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Autism spectrum disorder (ASD) is a group of disabilities with impairments in physical, verbal, and behavior areas. Regardless the growing frequency of autism, no medicine has been formed for the management of the ASD primary symptoms. The most frequently prescribed drugs are off-label. Therefore, there is necessity for an advance tactic for the treatment of autism. The endocannabinoid system has a central role in ruling emotion and social behaviors. Dysfunctions of the system donate to the behavioral deficits in autism. Therefore, the endocannabinoid system represents a potential target for the development of a novel autism therapy. Cannabis and associated compounds have produced substantial research attention as a capable therapy in neurobehavioral and neurological syndromes. In this review we examine the potential benefits of medical cannabis and related compounds in the treatment of ASD and concurrent disorders
... Conditions requiring specialist referral are usually persistent use despite recognition of harms, those with severe comorbid mental health problems, and those who are pregnant. [16] So, it does not appear to be an unrealistic goal to train PCDs in identifying and initiating management of cannabis use disorder at primary care. This would help in retaining these patients in the treatment program and regularly sensitize them to the potential harms of cannabis use. ...
... Limited evidence is available concerning pharmacological treatment [13,31]. Some clinicians recommend psychoeducation [32], but we know of no studies of the usefulness of this approach. Further research is needed to identify efficacious behavioral or pharmacological interventions. ...
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This chapter treats on the latest research on cannabis withdrawal syndrome. It summarizes the accumulating evidence concerning the cannabis withdrawal syndrome as a syndrome of clinical importance that encompasses specific withdrawal symptoms with a clear time course. It presents study findings on the withdrawal phenomenon and symptoms that show a fairly consistent picture largely in line with the cannabis withdrawal criteria in the DSM-5. Finally, the chapter treats implications for clinical treatment and future research regarding identification of efficacious behavioral or pharmacological interventions for withdrawal symptoms, and other substance-related problems.
... For certain doses, cannabis has been related to increased rates of myocardial infarction and cardiac arrhythmias (15). However, a clinical review recommended the management of cannabisrelated disorders without mentioning cardiovascular disorders (16). Cannabis has been added to the risk factors of cardiac disease in another study (17). ...
Article
Background: Cannabis is one of the most widely used illicit substances worldwide, and it has the highest prevalence among drugs used in Egypt. Objectives: The aims were to evaluate whether the use of cannabis is a risk factor of acute coronary heart disease in low-risk, young males and to compare the cardiac pathological changes between cannabis exposed and non-exposed ischemic patients. Methods: This was a cross-sectional study that was performed on 138 male patients, aged ≤ 40 years, with acute myocardial infarction who were admitted to the Cardiac Care Unit at the University Hospital. Urine samples were submitted for toxicological analysis using a homogenous enzyme immunoassay technique to determine the substance of use. The patients were divided into three groups: group 1 (n = 23), cannabis-positive only patients; group 2 (n = 28), patients positive for any other substance of use; and group 3 (n = 34), patients negative for any substance of use. Results: Smoking was prominent, whereas group 1 had no other risk factors. In groups 1 and 2, ST-segment elevation myocardial infarction (STEMI) was dominant, whereas no ST-segment elevation myocardial infarction (NSTEMI) was prominent in group 3. Ischemic resting wall motion abnormalities were presented in 47.8% of group 1 and in only 11.8% of group 3. None of group 1 had normal coronaries, whereas 14.3% of group 3 had normal coronaries. Significant changes in echocardiography and angiography were observed between group 1 and other groups. Conclusion: Cannabis smoking could be a potential risk factor for the development of cardiac ischemia.
... R egular use of cannabis may be associated with a variety of health, emotional, behavioural, social and legal problems particularly in young and in severely mentally ill people (Winstock, Ford, & Witton, 2010). Of the various mental conditions, the most studied are depression, anxiety and psychosis, the latter with more emphasis due to its clinical relevance (Arendt, Rosenberg, Foldager, Perto, & Munk-Jorgensen, 2005;Caspi et al., 2005;de Irala, Ruiz, & Martinez, 2005;Macleod, & Hickman, 2010;Moore et al., 2007;Veen et al., 2004). ...
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This cross-sectional study aims to determine lifetime prevalence of psychiatric disorders (including substance use disorders, -SUD and other non substance use disorders, –Non-SUD) among 289 young (1830 years) regular cannabis users, during the last year, in non-clinical settings in Barcelona. The Spanish version of the Psychiatric Interview for Substance and Mental Disorders (PRISM) was administered. Only 28% of the participants did not present any psychiatric disorder; while 65% had some SUD, the most common related to cannabis use (62%). Nearly 27% presented a non-SUD disorder. A younger age of initiation on alcohol use was associated with the presence of some SUD. Having consumed a greater number of “joints” in the last month was associated with the presence of both psychiatric disorders (SUD and non-SUD). While three quarters of subjects with non-SUD disorders had received some kind of treatment, only 28% of those with any SUD had received treatment. Given the low perception for need of treatment, there is a need for prevention strategies and to be able to offer therapies specifically tailored targeting young cannabis users.
... Because substance use experimentation is normative and typical in this age range (Shedler and Block, 1990), abstinence is rarely a clinically useful (or tenable) treatment target. Instead, when treating adolescents, many clinicians target consumption at less hazardous levels and in less harmful ways (e.g., harm reduction) (Winstock et al., 2010) as their target treatment outcome. ...
Article
Many clinicians who provide mental health treatment find developmental neuroscience discoveries to be exciting. However, the utility of these findings often seem far removed from everyday clinical care. Thus, the goal of this article is to offer, in the context of adolescent mental health, a bridge to connect the fields of applied adolescent treatment and developmental neuroscience investigation. Concretely, an overview of the relevance of developmental neuroscience in adolescent direct practice is provided. A rationale is offered for how and why the integration of neuroscience into the study of adolescent treatment response could benefit adolescent treatment outcomes. Finally, a series of practical suggestions is generated for improving integration of basic science and psychotherapy research, to enhance collaborative, interdisciplinary work that ultimately advances treatment response for this important clinical population.
... Although cannabis misuse is highly frequent worldwide with about 10 percent of the regular users developing cannabis dependence during their lifetime (Winstock et al., 2010), no approved pharmacological treatment for cannabis dependence exists so far but several psychotherapeutic treatment approaches provide some evidence for effectiveness Swift, 2009, Denis et al., 2006). The most important treatment approach is still the gradual reduction of cannabis intake with symptom control in order to avoid relapse and self-medication of withdrawal symptoms (Reed et al., 2015). ...
Chapter
Substance use disorders (SUD) are complex and often chronic diseases with negative health outcomes and social consequences. Pharmacological treatment options for SUD can be separated in medications for (i) intoxication, (ii) withdrawal, and (iii) reduction of use together with relapse prevention. This chapter will focus on approved or clinically established pharmacological strategies suited to manage symptoms of withdrawal, and to reduce substance use or to promote abstinence. Hereby SUD involving alcohol, nicotine, stimulants, and opioids are primarily discussed as these substances are considered most harmful for both the individual and the society. Moreover, the pharmacotherapy of SUD related to the use of cannabis, benzodiazepines, and gamma-hydroxybutyrate is also briefly reviewed. Since most approved pharmacological treatment options show only moderate effect sizes especially in the long term, the development of new treatment strategies including new drugs, new combinations of available compounds, and biomarkers for response prediction is still warranted.
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Background and overview: There is a deficit in clinical research on the potential risks involved in treating dental patients who use cannabis for either medicinal or recreational purposes. The aim of this case report is to illustrate the need for additional education for oral health care professionals so they can understand the wide variety of available cannabis options and their potential effects on dental treatment. Case description: A 27-year-old man sought care at the dental clinic with a nonrestorable molar requiring extraction. During the review of his medical history, the patient reported taking a "dab" of marijuana approximately 5 hours before his appointment. Because of the admission of recent illicit drug use, no treatment was rendered. The patient was offered an appointment the next day but he refused, citing bias in regard to his cannabis use. Conclusions and practical implications: The number of Americans using marijuana is increasing rapidly. Twenty-three states and the District of Columbia have laws legalizing cannabis to some degree, and Alaska, Colorado, Oregon, and Washington have legalized marijuana for recreational use. This drastic upswing in availability and usage will require dentists to address the possible effects of cannabis on dental practices. It is imperative that dental care providers make clinical decisions based on scientific evidence regarding the pharmacologic and psychological effects of marijuana, not on the societal stigma associated with illegal drug use. Dentists should be familiar with popular delivery systems and understand the differences between various marijuana options. Clinical guidelines may need to be developed to help providers assess the patient's degree of cognitive impairment. Dentists should be able to advise patients on the potential consequences of this habit on their oral health.
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Cannabis is the most widely used illicit drug in the developed world. Despite this, there is a paucity of research examining its long-term effect on the human brain. To determine whether long-term heavy cannabis use is associated with gross anatomical abnormalities in 2 cannabinoid receptor-rich regions of the brain, the hippocampus and the amygdala. Cross-sectional design using high-resolution (3-T) structural magnetic resonance imaging. Participants were recruited from the general community and underwent imaging at a hospital research facility. Fifteen carefully selected long-term (>10 years) and heavy (>5 joints daily) cannabis-using men (mean age, 39.8 years; mean duration of regular use, 19.7 years) with no history of polydrug abuse or neurologic/mental disorder and 16 matched nonusing control subjects (mean age, 36.4 years). Volumetric measures of the hippocampus and the amygdala combined with measures of cannabis use. Subthreshold psychotic symptoms and verbal learning ability were also measured. Cannabis users had bilaterally reduced hippocampal and amygdala volumes (P = .001), with a relatively (and significantly [P = .02]) greater magnitude of reduction in the former (12.0% vs 7.1%). Left hemisphere hippocampal volume was inversely associated with cumulative exposure to cannabis during the previous 10 years (P = .01) and subthreshold positive psychotic symptoms (P < .001). Positive symptom scores were also associated with cumulative exposure to cannabis (P = .048). Although cannabis users performed significantly worse than controls on verbal learning (P < .001), this did not correlate with regional brain volumes in either group. These results provide new evidence of exposure-related structural abnormalities in the hippocampus and amygdala in long-term heavy cannabis users and corroborate similar findings in the animal literature. These findings indicate that heavy daily cannabis use across protracted periods exerts harmful effects on brain tissue and mental health.
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Anxiety reactions and panic attacks are the acute symptoms most frequently associated with cannabis use. Understanding the relationship between cannabis and anxiety may clarify the mechanism of action of cannabis and the pathophysiology of anxiety. Aims of the present study were to review the nature of the relationship between cannabis use and anxiety, as well as the possible clinical, diagnostic and causal implications. Systematic review of the Medline, PsycLIT and EMBASE literature. Frequent cannabis users consistently have a high prevalence of anxiety disorders and patients with anxiety disorders have relatively high rates of cannabis use. However, it is unclear if cannabis use increases the risk of developing long-lasting anxiety disorders. Many hypotheses have been proposed in an attempt to explain these relationships, including neurobiological, environmental and social influences. The precise relationship between cannabis use and anxiety has yet to be established. Research is needed to fully clarify the mechanisms of such the association.
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Cannabis is the most widely used illicit drug in the world. Treatment admissions for cannabis use disorders have risen considerably in recent years, and the identification of medications that can be used to improve treatment outcomes among this population is a priority for researchers and clinicians. To date, several medications have been investigated for indications of clinically desirable effects among cannabis users (e.g. reduced withdrawal, attenuation of subjective or reinforcing effects, reduced relapse). Medications studied have included those: (i) known to be effective in the treatment of other drug use disorders; (ii) known to alleviate symptoms of cannabis withdrawal (e.g. dysphoric mood, irritability); or (iii) that directly affect endogenous cannabinoid receptor function. Results from controlled laboratory studies and small open-label clinical studies indicate that buspirone, dronabinol, fluoxetine, lithium and lofexidine may have therapeutic benefit for those seeking treatment for cannabis-related problems. However, controlled clinical trials have not been conducted and are needed to both confirm the potential clinical efficacy of these medications and to validate the laboratory models being used to study candidate medications. Although the recent increase in research towards the development of pharmacotherapy for cannabis use disorders has yielded promising leads, well controlled clinical trials are needed to support broad clinical use of these medications to treat cannabis use disorders.
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Our aim was to determine the combined and independent effects of tobacco and marijuana smoking on respiratory symptoms and chronic obstructive pulmonary disease (COPD) in the general population. We surveyed a random sample of 878 people aged 40 years or older living in Vancouver, Canada, about their respiratory history and their history of tobacco and marijuana smoking. We performed spirometric testing before and after administration of 200 microg of salbutamol. We examined the association between tobacco and marijuana smoking and COPD. The prevalence of a history of smoking in this sample was 45.5% (95% confidence interval [CI] 42.2%-48.8%) for marijuana use and 53.1% (95% CI 49.8%-56.4%) for tobacco use. The prevalence of current smoking (in the past 12 months) was 14% for marijuana use and 14% for tobacco use. Compared with nonsmokers, participants who reported smoking only tobacco, but not those who reported smoking only marijuana, experienced more frequent respiratory symptoms (odds ratio [OR] 1.50, 95% CI 1.05-2.14) and were more likely to have COPD (OR 2.74, 95% CI 1.66-4.52). Concurrent use of marijuana and tobacco was associated with increased risk (adjusted for age, asthma and comorbidities) of respiratory symptoms (OR 2.39, 95% CI 1.58-3.62) and COPD (OR 2.90, 95% CI 1.53-5.51) if the lifetime dose of marijuana exceeded 50 marijuana cigarettes. The risks of respiratory symptoms and of COPD were related to a synergistic interaction between marijuana and tobacco. Smoking both tobacco and marijuana synergistically increased the risk of respiratory symptoms and COPD. Smoking only marijuana was not associated with an increased risk of respiratory symptoms or COPD.
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Client ambivalence is a key stumbling block to therapeutic efforts toward constructive change. Motivational interviewing—a nonauthoritative approach to helping people to free up their own motivations and resources—is a powerful technique for overcoming ambivalence and helping clients to get "unstuck." The first full presentation of this powerful technique for practitioners, this volume is written by the psychologists who introduced and have been developing motivational interviewing since the early 1980s. In Part I, the authors review the conceptual and research background from which motivational interviewing was derived. The concept of ambivalence, or dilemma of change, is examined and the critical conditions necessary for change are delineated. Other features include concise summaries of research on successful strategies for motivating change and on the impact of brief but well-executed interventions for addictive behaviors. Part II constitutes a practical introduction to the what, why, and how of motivational interviewing. . . . Chapters define the guiding principles of motivational interviewing and examine specific strategies for building motivation and strengthening commitment for change. Rounding out the volume, Part III brings together contributions from international experts describing their work with motivational interviewing in a broad range of populations from general medical patients, couples, and young people, to heroin addicts, alcoholics, sex offenders, and people at risk for HIV [human immunodeficiency virus] infection. Their programs span the spectrum from community prevention to the treatment of chronic dependence. All professionals whose work involves therapeutic engagement with such individuals—psychologists, addictions counselors, social workers, probations officers, physicians, and nurses—will find both enlightenment and proven strategies for effecting therapeutic change. (PsycINFO Database Record (c) 2012 APA, all rights reserved)
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For over two decades, cannabis, commonly known as marijuana, has been the most widely used illicit drug by young people in high-income countries, and has recently become popular on a global scale. Epidemiological research during the past 10 years suggests that regular use of cannabis during adolescence and into adulthood can have adverse effects. Epidemiological, clinical, and laboratory studies have established an association between cannabis use and adverse outcomes. We focus on adverse health effects of greatest potential public health interest-that is, those that are most likely to occur and to affect a large number of cannabis users. The most probable adverse effects include a dependence syndrome, increased risk of motor vehicle crashes, impaired respiratory function, cardiovascular disease, and adverse effects of regular use on adolescent psychosocial development and mental health.