Cannabis Use Disorder

Cannabis Use Disorder

• In the 1960s and 1970s, cannabis was not regarded as a drug of dependence. 
• It did not seem to produce tolerance or withdrawal syndrome, as markedly seen with alcohol and opioids. 
• Subsequently, because of change or a broader aspect of dependence was applied, it was also considered as substance use disorder. 

Diagnosis of Cannabis Use Disorder

CRITERIA A: It is a problematic pattern of substance use leading to clinically significant impairment/distress with at least two symptoms within 12 month period:

Impaired Control in Cannabis Use Disorder

• The substance is taken in larger amounts or over a longer period than intended.
• Persistent desire or unsuccessful efforts to cut down or control cannabis use.
• Excessive time spent in activities to obtain, use, or recover from its effects.
• Craving or strong desire to use cannabis.

Social Impairment in Cannabis Use Disorder

• Recurrent use of failing to fulfill major role obligations at work, school, or home.  
• Continued use despite having persistent or recurrent social or interpersonal problems that are caused or increased by cannabis effects.
• Important social, occupational, or recreational activities are given up or reduced due to cannabis. 

Risky Use of Ccannabis

• Recurrent cannabis use in physically hazardous situations. 
• Continued use despite knowledge of persistent physical or physiological problems likely to be caused by cannabis.

Tolerance To Cannabis - Tolerance Is Defined By Either Of Them

• The increased amount required to achieve intoxication or the desired effect.
• Diminished effect with continued use of the same amount. 

Withdrawal To Cannabis- Withdrawal Manifests By Either Of Them

• Characteristic withdrawal syndrome for cannabis.
• Cannabis (or a closely related substance) is taken to relieve or avoid withdrawal symptoms. 

Specifiers May Be Added:

• In early remission (that means the person is not fulfilling the criteria that he was fulfilling before cannabis use). Duration is 3 months to less than 12 months. 
• In sustained remission, the duration is longer, i.e., 12 months or more.
• In a controlled environment. 

Risk of Cannabis Use Disorder

• Those who use cannabis daily over weeks to months are more likely to develop cannabis use disorder. 
• The risk is 1 in 10 with anyone who ever has used cannabis. 
• There is an increase in risk with increased frequency of use. 
• For those who use it more than a few times, the risk is 1 in 5 to 1 in 3. 
• If someone has a history of daily use, the risk is 1 in 2. 
• Higher risk is associated with an earlier age of 1^st time use. The risk is 1 in 6 who use cannabis during their mid-adolescence.
• Also, the risk is higher if used more often for a longer period. 

Other Risk Factors Of Cannabis Use

• Poor academic achievement.
• Deviant behaviour in childhood and adolescence.
• Non-conformity or rebelliousness.
• Personal distress and maladjustments.
• Earlier use
• Poor parental relationships.
• Parental history of drug and alcohol problems. 

Cannabis Intoxication

Acute Effects Of Cannabis Intoxication (Behavioural and Cognitive Effects)

• There may be a high feeling of mild euphoria. 
• There is also a feeling of relaxation and perceptual alterations, including time distortion (slowing of time).
• Ordinary experiences are intensified (such as eating and watching films).
• Acute administration of cannabis may shorten sleep latency. 
• There is enhancement in the slow wave sleep and suppression in the REM sleep. 
• In chronic users, tolerance may develop to sleep-inducing and slow-wave sleep enhancing.
• Infectious laughter, talkativeness, and increased sociability may develop in social settings.
• In high doses, the person may develop depersonalization and derealization. 
• Cognitive changes are seen, and impairments in short-term memory, attention, motor skills, reaction time, and motor coordination may be affected.
• These cognitive changes may cause impairment, especially in tasks requiring sustained attention. This may impair functions involving driving a vehicle or operating machinery, increasing the risk of motor vehicle accidents. 
• A dose-response relationship is seen between THC in blood and the risk of accident. 
• A combination of THC and alcohol may show marked impairment and increase the risk of an accident. 
• Pathological symptoms like bad trips, psychosis, and delirium may appear. 
• A bad trip is an unpleasant experience characterized by restlessness, fear, panic symptoms, and feeling of going crazy. 
• Transient paranoid ideation may be seen. At high doses, psychotic symptoms may appear, such as delusions, hallucinations, visual and auditory hallucinations, delusional ideas, and thought disorders. 
• At high doses, delirium may appear. High doses may impair the level of consciousness in patients with marked defects in cognitive functions. 

Physiological Effects Of Cannabis Intoxication

Effects on the Gastrointestinal Tract

• GI effects such as dry mouth and an increase in appetite may be there. 
• At low to moderate doses, a decrease in nausea may be seen. 
• At high doses or less, experienced users may report nausea or vomiting. 
• There may be excessive thirst or constipation. 

Effects on the Cardiovascular System

• The most immediate of smoking cannabis is an increase in heart rate by 20-50%, and this occurs within a few to 15 minutes. 
• Blood pressure changes. In sitting, it increases, and in standing, it decreases. 
• A sudden change of posture from lying to standing. Many times, patients may complain of postural hypotension, the feeling of lightheadedness, and faintness. This often is the earliest indication of drug effects in naive users. 
• Tolerance may develop to the CV effects. Chronic use may not be associated with any cardiac health risk. 

Effects on Ophthalmological system

• Redness of the eyes because of an increase in the cardiac output and dilation of small blood vessels.  
• Decrease in intra-ocular pressure. 
• Rarely it may cause photophobia and nystagmus. 
• At high doses ptosis and miosis may also be seen. 

Effects on the Respiratory System

• There is an increase in carboxyhemoglobin. 
• There is irritation in the respiratory tract (retention of TAR).
• There may be mild bronchoconstriction subsequently, it causes bronchodilatation. 

Duration Of Symptoms In Cannabis Intoxication

• When cannabis is smoked, the euphoric effects may peak in 30 minutes. 
• These symptoms may last for 2 to 4 hours. 
• Some motor or cognitive effects may last for 5 to 12 hours. 
• It is seen that 2-3 times oral cannabis is required to be as potent as smoked cannabis. 

Criteria In Dsm 5 For Cannabis Intoxication

1. There should be recent use of cannabis.
2. Clinically significant problematic behavioural or psychological changes. E.g., impaired motor coordination, euphoria, anxiety, sensation of slowed time, impaired judgment, and social withdrawal. These changes develop during or shortly after cannabis use. 
3. Two or more signs and symptoms within two hours of cannabis use: conjunctival injection, increase in appetite, dry mouth, and tachycardia. 
4. These signs and symptoms are not attributable to another medical condition and are not better explained by another mental disorder, including intoxication with another substance. 

Treatment Of Cannabis Intoxication

• Symptoms are mostly mild and self-limiting. So, reassurance and supportive care are enough in the management.
• Patients should be placed in a calm, cool, and quiet atmosphere. Optimal lighting in the room should be there.  
• Pharmacotherapy may also be used. Pharmacotherapy is used in severe, distressing, anxiety, unmanageable, disruptive, and psychotic symptoms. Pharmacotherapy given according to standard guidelines of  MOHFW GOI 2020
  • Preferably, short-acting benzo diazapines can be used. 
  • Low doses of antipsychotics can be used. Preferably 2^nd generation drug like Quetiapine. 
  • Propranolol may be used. Usually, the dose is 40-80 mg/day for 1-2 days. 

Cannabis Withdrawal

• Cannabis withdrawal is less intense as compared to other substances because it has a long half-life (plasma t1/2 is more than 50 hours) and there is a complex metabolism of cannabis.
• Usually, withdrawal symptoms are seen when a person abruptly stops taking high doses of cannabis. 
• When there is cessation use in daily cannabis users, most symptoms onset within 1^st to 24 hours of cessation peak within 1^st week and last for 1 to 2 weeks.
• Sleep difficulty may last for more than 30 days. 
• The most common symptoms seen with cannabis withdrawal are irritability, anxiety, and depression. 
• Certain other symptoms are cannabis cravings, insomnia, anorexia, weight loss, mild nausea, disturbed or vivid dreams, and nervousness. 
• Restlessness, headache, chills, stomach pain, sweating and tremors may be associated with withdrawal symptoms. 
• Sleep difficulties may occur. 
• In polysomnography studies, it may be seen that there is a decrease in slow-wave sleep and an increase in REM sleep. 

Treatment Of Cannabis Withdrawal

• Symptoms are usually transient and self-limiting. So, reassurance and supportive care may be required. 
• Pharmacotherapy may be required for severe and distressing symptoms. Pharmacotherapy is given according to standard guidelines of  MOHFW GOI 2020
  • Long-acting benzodiazepines like chlordiazepoxide and diazepam can be used. 
  • For insomnia zolpidem can be used. Usually, the dose is 5-10 mg at night.
  • Baclofen can be used as a second-line treatment. And the dose is 40 mg/day. Duration of treatment may be 7 days. 
  • CB1 agonists may be used. Dronabinol (synthetic THC) can be used, its dose is 20-90 mg.  A combination of Lofexidine- α₂ agonist and dronabinol may be used in managing the withdrawal.  Nabilone (6-8 mg/day) has better bioavailability. Nabiximole can be used (300-600 mg/day), which has a 1:1 ratio of Δ9THC: CBD, it is an oromucosal botanically derived spray. 
  • Research molecules like cannabinoid antagonists (SR141716A) can be used. Cannabis extract such as Sativex (which contains an equal amount of THC and CBD) can relieve withdrawal symptoms. 

Also Read: Management Of Alcohol Use Disorder

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