weedUseDisorder Flashcards

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 On average, .....of Canadians (4.4 million people) over the age of 15 have used cannabis in the past 12 months


 15-19 years: 19%
 20-24 years: 33%
 25 years and older: 13%


Cannabis Pharmacology

Consumed in many forms:
 Smoked (combusted)
 Vaporized
 Made into oils/gummies (edibles)
 Used in cooking/baking
 Concentrated into hash and shatter and then smoked

-there are 2 main active

 Delta-9-Tetrahydrocanabinol (aka THC)
 Cannabidiol (aka CBD)

 There are also thousands of other compounds, some active, some not



THC is the main psychoactive compound found in cannabis
 THC-rich resins can be extracted from the cannabis plant



 Shatter is basically crystalized THC resin.

Preparation of shatter is also dangerous as it requires high temperatures so
butane is often used



Substance induced psychosis is a real concern here

because THC is fat soluble, it stays in the body for a long time, making the
psychosis difficult to treat


Endocannabinoid System:

Two primary receptors in this system:(oncell surfaces)
 CB1
 CB2

CB1 receptors are found in the following areas in the body:
 Cerebral cortex
 Hippocampus
 Basal ganglia
 Hypothalamus
 Anterior cingulate gyrus
 Intrinsic and extrinsic neurons in the GI tract


CB2 receptors are found in?

 Immune system (primarily)
 Blood vessel cells/blood cells


Action of CB Receptors

-Couple with G-Protein
-Activation on presynaptic cells→ reduction in release of inhibitory and
excitatory NTs


CB1 receptor:
distributed in the brain

-Reduces release of Ach, DA, GABA, glutamate, NA
- Ultimately leads to reduction in signaling of pain


CB2 receptor:

 Located on immune cells
 Binding of ligand leads to reduction in release of cytokines
 Ultimately leads to regulation of the immune system


Acute THC Intoxication

Altered, more intense senses
 Impaired memory and inability to
divide attention
 Impaired body movements; body
 Changes in mood (can be more
mellow or more elevated/anxious)
 Increased appetite
 Impaired coordination/balance
 Tachycardia
 Hypertension
 Dilated pupils and red eyes
 Dry mouth/throat


 With high dose or potency
cannabis or extracts- users can experience......

 Hallucinations
 Delusions
 Psychosis
 Shatter specifically:
 Burns due to high temp required to
both create and to smoke/vaporize


Management of Acute THC Intoxication

Unintentional ingestion in children

More likely to have severe
 Hyperkinesis or deep coma
 CNS depression, including
respiratory depression is possible

 Cannabinoid-Induced Hyperemesis
 Should be on your radar in the case
of intractable vomiting
 More on this later


Mild intoxication

 Supportive care is usually all that’s
 Reduce stimulation in the room
 Reassure patient the symptoms will


management of Severe THC intoxication with agitation

-Benzodiazepines are first line
-May need to add other drugs
- Suspect shatter or multi-drug use
in this case


Long-Term Effects of Cannabis Use

Use before 25 years:

Has been shown to impact brain
 Can have long-term impacts on:
 Learning processes
 Thinking
 Memory
 Brain connections


Long-term cannabis use can also:

 Impact executive functioning
 Increase risk of psychosis,
depression, and anxiety
 Increase risk of lung conditions
including COPD and worsening
 Increase risk of Cannabinoid Induced


Cannabis in Pregnancy

-Primary active components: CBD and THC
- Both highly fat soluble
- Both cross placenta and into breastmilk (~10% maternal plasma concentration in
placenta with acute exposure, higher with repeat exposure)
- Cannabis available now MUCH more potent in terms of [THC] compared to 30
years ago
- Over 20% THC on average now compared to about 2% in the 1980s


SOGC (Society of Obstetricians and Gynaecologists of Canada) position: Cannabis in Pregnancy

-most commonly used recreational drug in pregnancy in Canada
 Most pregnant women (~70%) believe there is little to no risk in
using cannabis a few times per week during pregnancy, even in the first trimester
 SOGC position: safest amount of cannabis in pregnancy is NO
CANNABIS; “why risk it?”


Cannabis in Pregnancy: Impact on Outcomes

- In general, risk is unclear as the evidence is weak
- Use in pregnancy may be associated with increased risk of low birth weight
and preterm delivery
- Evidence complicated by polysubstance use as cannabis often consumed
simultaneously with tobacco
- Use while breastfeeding may be associated with increased risk of
- CV or mental health issues
- Learning development and behaviour issues


What is Cannabinoid-Induced
Hyperemesis Syndrome (CIHS)?

“Cannabinoid Hyperemesis Syndrome is characterized by chronic cannabis use, cyclical episodes of nausea and
vomiting, and frequent hot bathing.”


Symptoms of CIHS

what are the 3 phases?

 3 Phases:
 Prodrome-normal eating habits/continued cannabis use. Hyperemesis-nausea/vomiting/compulsive hot showers/ abdomina pain
 Recovery(follows active or supportive mgt)-restored aeting habits, relative wellness


Prodromal Phase

abdominal discomfort, early morning nausea, and anxiety about
 This phase can last months to years.
 Patients usually continue cannabis use and may increase it’s used due to the belief
that cannabis will help with their nausea


Hyperemesis Phase

episodes of nausea and vomiting.

 Intractable and renders the patient incapacitated.
 Patients can vomit profusely up to 5 times per hour.
 Accompanied by abdominal pain.
 Can last for hours to days.
 Marked weight loss (>5kg) and dehydration are common
 Learned behaviour of multiple hot showers per day to alleviate nausea and


Recovery Phase

all symptoms are mostly or completely resolved.
 Return to normal appetite and eating
 Restoration of normal body weight
 Restoration of normal bathing habits


Clues in the Diagnosis of CIHS

 The patient frequently uses cannabis or cannabinoids

 Symptoms are relieved by a hot shower or bath

 Symptoms are eliminated when cannabis/cannabinoid use ceases

 Age <50 y/o is most common

 Significant weight loss (>5kg)

 Symptoms are worst in the morning during a hyperemesis episode

 All lab tests, radiography, and endoscopy tests lack significant findings

 Bowel activity is normal


Rome IV Diagnostic Criteria for CIHS

-Must include all of the following:......

-Criteria fulfilled for the last 3 months with symptom onset at least 6 months
before diagnosis

-Supportive remarks:
May be associated with pathologic bathing behavior (prolonged hot baths or

1. Stereotypical episodic vomiting resembling cyclic vomiting syndrome (CVS) in
terms of onset, duration, and frequency
 2. Presentation after prolonged excessive cannabis use
 3. Relief of vomiting episodes by sustained cessation of cannabis use


Proposed Pathophysiology

 Dysregulation of the endocannabinoid system
 Genetic variation in metabolism of cannabinoids
 Altered thermoregulation and GI motility by the endocannabinoid and
endovanilloid systems
 Primary receptor involved = TRVP1
 Present on skin and in GIT
 Long term exposure of TRVP1 to cannabinoids can inactivate the receptor
 Leads to reduced gut motility→ nausea→ vomiting


Why all this talk about hot showers?

-The endocannabinoid system is involved in many different processes in the body
- CB1 receptors in the hypothalamus play a role in thermoregulation
- Cannabinoids cause a dose-dependent reduction in heat production
- Very high doses can lead to hypothermia and nausea/vomiting
- Diversion of blood from GIT to skin to cool down→ reduced N/V
- Hot showers (and capsaicin) work on both the endocannabinoid and
endovanilloid systems together, increasing gut motility


trtment with hot showers or capsaicin

1. prolonged exposure to cannabinoids inactivates the TRPV1 receptor.

2.TRPV1 inactivation leads to nausea and emesis both via central effects and vagal afferents.

3.TRPV1 inactivation alters gastric motility.

4.cutaneous heat or capsaicin exposure normalizes gastric motility via activation of TRPV1


Evidence for Treatments:

 The only treatment that has consistently been shown to work is cannabis
cessation and this paper reinforced that.


a new pilot study by dean et al.

Not amazing
 Well done but still a pilot
 30 mins may be too soon to see benefit
 Overall, trial shows trend to benefit of treatment with capsaicin


DSM-V Criteria: Substance Use Disorder

“A problematic pattern of [substance] use leading to
clinically significant impairment or distress, as manifested
by at least 2 of the following, occurring within a 12-month
-Impaired control
- Social impairment
- Risky use
- Pharmacological criteria


Diagnosis of Cannabis Use Disorder

A problematic pattern of cannabis use leading to clinically significant impairment or distress, as
manifested by at least two of the following, occurring within a 12-month period:
1. Cannabis is often taken in larger amounts or over a longer period than was intended.
2. There is a persistent desire or unsuccessful efforts to cut down or control cannabis use
3. A great deal of time is spent in activities necessary to obtain cannabis, use cannabis, or recover from its
4. Craving, or a strong desire or urge to use cannabis.
5. Recurrent cannabis use resulting in a failure to fulfill major role obligations at work, school, or home.
6. Continued cannabis use despite having persistent or recurrent social or interpersonal problems caused or
exacerbated by the effects of cannabis.
7. Important social, occupational, or recreational activities are given up or reduced because of cannabis use.
8. Recurrent cannabis use in situations in which it is physically hazardous.
9. Cannabis use is continued despite knowledge of having a persistent or recurrent physical or psychological
problem that is likely to have been caused or exacerbated by cannabis.
10. Tolerance, as defined by either of the following:
a) A need for markedly increased amounts of cannabis to achieve intoxication or desired effect.
b) Markedly diminished effect with continued use of the same amount of cannabis.
11. Withdrawal, as manifested by either of the following:
a) The characteristic withdrawal syndrome for cannabis (refer to Criteria A and B of the criteria set for cannabis
withdrawal, pp. 517–518).
b) Cannabis (or a closely related substance) is taken to relieve or avoid withdrawal symptoms.


Treatment of Cannabis Use Disorder

Non-pharmacological treatments:

 Drug/addiction counseling
 Motivational interviewing
 Mutual help groups (e.g. Narcotics Anonymous)


Pharmacological treatments:

A few have been studied, to varying degrees of success:
- Gabapentin
- N-acetylcysteine (NAC)
- Nabiximols
- Cannabidiol
- Lots of others (topiramate, antidepressants, divalproex, atomoxetine, dronabinol, etc)
have largely been found to be no better than placebo


Gabapentin for Cannabis Use Disorder

-Thought to work in the amygdala and nucleus acumbens to help restore GABA
tone to normal levels
-Considered an anti-craving agent
- Has evidence for use in alcohol use disorder as an anti-craving agent,
especially in addition to naltrexone.
- Evidence in cannabis use disorder is mixed.


N-Acetylcysteine for Cannabis Use

 Antioxidant precursor to glutathione
 Impacts glutamate functioning in the brain
 Thought to impact cannabis use disorder by:
 Correcting glutamate dysregulation in the nucleus acumbens as a result of
substance use
 Upregulating the glutamate transporte GLT-1
 Thus removing excess glutamate from the nucelus acumbens
 Evidence has been mixed at best


Harm Reduction Measures for Cannabis Use

-any form of weed poses risks to your health.

-the earlier u begin the greater the risk start later in life.

-choose low strength prdts

-dont use synthetic cannabis products.

-smokin joints is harmful-to your lungs

-do not inhale or hold your breath

-limit use as much as possible

-weed use impairs your ability to drive.

-pple wit psychosis in their fam or pregnant shd not use

-avoind combining any of the risky behaviours-they increase the chances of harming your health.