THERAPEUTIC USES OF CANNABIS


Cannabis is currently used as a therapeutic product throughout the world.

The following benefits of cannabis have been documented around the world by various medical and government bodies.

  • Feeling of well-being
  • Increased sociability
  • Muscle relaxant
  • Analgesic effect
  • Appetite stimulation
  • Antiemetic effect
  • Anticonvulsant effect
  • Lower intraocular pressure

In Canada, section 56 of the Controlled Drugs and Substances Act gives Health Canada the discretionary power to grant an exemption for medical reasons to persons who consider that the use of cannabis is beneficial to their health.

Hence, many sick people in Canada have obtained Health Canada approval to smoke cannabis for therapeutic reasons; however, it is still illegal to grow cannabis.

Health Canada has awarded funds for clinical trials to assess the effectiveness of marijuana.

  • Community Research Initiative of Toronto (CRIT): usefulness of cannabis among individuals with HIV/AIDS
  • McMaster University, Hamilton: usefulness of cannabis among patients with epilepsy
  • Multiple Sclerosis Clinic, Saskatoon: evaluation of the effects of cannabis on muscle spasticity among sufferers of multiple sclerosis and
  • G.F. Strong Rehabilitation Centre, Vancouver: evaluation of the effects of cannabis on spasticity of limbs among individuals with spinal cord injuries

 

N.B.: The mode of action of THC is still not properly understood.


 ACUTE CANNABIS INTOXICATION

Central effects

 

  • Euphoria: feeling of well-being and satisfaction
  • Feelings of calmness and relaxation
  • Loquacity
  • Gaiety that may include infectious laughter
  • Freedom from care
  • Sociability
  • Increased self-confidence
  • Distorted perception of time, space and self-image
  • Heightened sensory perceptions
  • Impaired short-term memory, attention and concentration
  • Impaired ability to complete complicated tasks
  • Impaired balance reflexes and motor co-ordination (driving affected)
  • Increased appetite (especially for sweet foods)
  • Increased libido

 

Less frequently:

  • Anxiety
  • Dizziness
  • Nausea
  • Convulsions

 

 

PERIPHERAL EFFECTS

  • Orthostatic hypotension
  • Tachycardia
  • Bronchodilation
  • Red eyes
  • Dry mouth

 

OVERDOSE

  • Drowsiness
  • Disorientation
  • Confusion
  • Cognitive disorganization
  • Impaired judgment
  • Hallucinations
  • Paranoia
  • Rarely, toxic psychosis (especially among predisposed individuals)

 

 CHARACTERISTICS OF THE PROGRESSION OF EFFECTS

Smoking cannabis

  • Very rapid onset of effect (few minutes)
  • Peak effect after 30 minutes
  • Duration of effect: 2 to 4 hours (and residual effects)

 

Ingesting cannabis

  • Slower onset of effect
  • More progressive and prolonged effects
  • Less euphoria

 

 INTERVENTION IN THE EVENT OF ACUTE INTOXICATION

  • Calm and reassure the patient
  • Dedramatize the situation
  • If necessary, sedate moderately with a benzodiazepine

N.B.:

  • These problems are not life-threatening
  • There is no antidote for cannabis, and no specific medical treatment

 

CHRONIC EFFECTS

  • Impaired memory, attention and concentration (reversible)
  • Amotivational syndrome: passivity, decreased initiative, apathy, loss of interest
  • Variable effect on sexual function (in some cases, decreased fertility in males and females)
  • Respiratory problems resulting from inhalation:
    • Pharyngitis, asthma, bronchitis, emphysema
    • More harmful than tobacco because the tar contained in cannabis smoke contains a higher concentration of carcinogenic agents, thereby resulting in an increased risk of lung cancer
  • Decreased resistance to infection

 

TERATOGENICITY

* Heavy cannabis use during pregnancy may impair fetal development

* Possibility of fetal death, premature birth, organ malformations, failure to thrive, cardiac toxicity, and impaired immune system

 

TOLERANCE AND PHARMACODEPENDENCE

  • Development of sensitization resulting from the transformation of THC into more active 11-hydroxy-THC by the liver
  • Little tolerance among occasional users
  • Significant tolerance if doses and frequency of use are high
  • Minimal physical dependence
  • Psychological dependence may be significant
  • Withdrawal symptoms observed among chronic users of large doses
  • Withdrawal symptoms: anxiety, restlessness, nervousness, irritability, insomnia, dysphoria, increased reflexes, headaches, sweating, loss of appetite, nausea, and intestinal cramps

 

LYSERGIC ACID DIETHYLAMIDE

(LSD or "acid") 

  • Synthesized from the lysergic acid found in a parasitic fungus of various grasses
  • Sold in tablet, capsule or liquid form
  • Extremely powerful hallucinogenic
  • Typical dose: 50 to 100 mg by mouth
  • Progression of effects when taken by mouth:
  1. Onset of effect: 30 to 60 minutes after ingestion
  2. Peak effect after 2 to 3 hours
  3. Duration of effect: 2 to 12 hours
  • No recognized therapeutic potential

 

ACUTE LSD INTOXICATION

Central effects

  • Euphoria
  • Agitation
  • Altered short-term memory
  • Impaired thinking and concentration
  • Increased sensory acuity
  • Hallucinations
  • Altered perception of self, shapes, colours, time and space
  • "Bad trip": anxiety, feelings of depersonalization, emotional instability, feeling of loss of control over self and environment, panic, feeling of persecution, confusion that develop into psychosis, potentially dangerous behaviour, tendency for self-destructive behaviour
  • Dizziness and lack of coordination
  • Convulsions

 

Peripheral effects

  • Blurred vision, mydriasis
  • Hypertension, tachycardia, palpitations
  • Hyperthermia
  • Facial flushing, goosebumps
  • Sweating
  • Nausea

 

TREATMENT OF ACUTE LSD INTOXICATION

  • Place the patient in a quiet setting with soft lighting, reassure the patient and Dedramatize the situation
  • Generally speaking, no medication is necessary

  • if fever external cooling and antipyretic


  • if convulsions diazepam, administered intravenously


  • if agitatedbenzodiazepine, administered orally

 

N.B. * Antipsychotic drugs are used less and less frequently because they tend to provoke convulsions.

* If an antipsychotic is necessary, avoid phenothiazines (e.g.: chlorpromazine or Largactil tm), which can provoke acute suicidal depression.

* There are no known deaths from LSD overdose.

 

CHRONIC EFFECTS OF LSD

  • Amotivational syndrome: passivity, decreased initiative, apathy, loss of interest
  • Anxiety
  • Impaired memory
  • Mood disorders (rarely: prolonged depression)
  • "Flashbacks" = euphoria and hallucinations may recur spontaneously days, weeks or months later
  • Psychosis (especially among predisposed individuals)

 

 

TOLERANCE AND PHARMACODEPENDENCE

  • Tolerance to LSD’s hallucinogenic effects develops after a few days of consumption and disappears just as quickly
  • Cross-tolerance with other hallucinogens
  • No physical dependence
  • Possible psychological dependence, intensity varies

 

TERATOGENICITY

  • Fetal defects
  • Spontaneous abortion

 

OTHER HALLUCINOGENS SIMILAR TO LSD

Mescaline: (powder, tablets, capsules)

  • Comes from the peyote cactus (Mexican cactus) or is synthesized
  • Compared with LSD: less severe central effects and more pronounced peripheral effects

Usual dose: 300 to 500 mg (by mouth)

 

Psilocybin: (mushrooms, capsules)

  • Extract of several mushrooms, including the psilocybe. Effects similar to LSD, but less intense and more pleasant.

Usual dose: 5 to 60 mg (by mouth)

 

 HALLUCINOGENIC STIMULANTS (synthetic drugs)

Dimethoxymethamphetamine (DOM, STP): (white powder)

  • Hallucinogenic effects similar to LSD
  • Significant peripheral effects

Usual dose: 3 to 10 mg (by mouth, snorted or injected)

 

Dethylenedioxyamphetamine (MDA, "love drug"): (white or brown powder, tablets)

  • Effects similar to MDMA, but longer and less pleasant

Usual dose: 100 mg (by mouth)

 

Methylenedioxymethamphetamine (MDMA, "Ecstasy", "Adam"): (white powder, tablets)

  • Ver mildly hallucinogenic

Usual dose: 40 to 150 mg (by mouth)

 

DISSOCIATIVE GENERAL ANAESTHETICS

Phencyclidine (PCP, "angel dust", "mess", "peace pills")

(powder of varied colour, tablets, capsules, crystals, paste, liquid)

  • Often sold under false names
  • Found in or instead of various hallucinogens (e.g.: mescaline)
  • Incorporated in several drugs (e.g.: marijuana, cocaine)
  • No real therapeutic potential

Usual dose: 1 to 5 mg (swallowed, smoked, snorted or injected)

 

 

Symptoms of acute PCP intoxication

  • Muscle stiffness, decreased responsiveness, slow and deep breathing
  • Fixed stare, stupor, mutism, psychosis, hallucinations (may appear 4 to 6 days after use)
  • Possibility of violent behaviour (verbal and physical)
  •  

 

TREATMENT OF ACUTE PCP INTOXICATION

  • Mild intoxication
    • Protect the subject against self
    • Calm and reassure subject
  • Severe intoxication
    • Intensive medical support (PCP is more dangerous than hallucinogens)
  • Period of observation: 4 to 6 hours
  • Treatment of complications
    • Severe agitation: diazepam (Valium tm) or haloperidol (Haldol tm)
    • Convulsions: diazepam (Valium tm) or phenytoin (Dilantin tm)
    • Arrhythmia or hypertension: propranolol (Inderal tm)

 

 

TOLERANCE AND PHARMACODEPENDENCE TO PCP

 

  • Significant tolerance if subject is a chronic user
  • Only hallucinogen for which self-administration has been observed among animals

 

PCP WITHDRAWAL

  • Terror, tremors, extreme nervousness, chronic severe anxiety, impaired thought processes and short-term memory, persistent speech problems
  • "Flashbacks" = euphoria and hallucinations may recur spontaneously days, weeks or months later
  • Depression

 

 

GENERAL APPROACH IN THE EVENT OF A "BAD TRIP"

  • Reassure and calm the subject (hold hand, gently rub back)
  • Remove from sources of agitation (crowds, very bright or very noisy places)
  • Do not attempt to bring subject back to a normal train of thought (may result in further confusion)
  • Convince subject that this state is temporary, that subject is not going crazy and that he/she is with people who will take care of him/her without being critical or hostile
  • Encourage subject to accept temporary state, that everything will return to normal, that this is not a mental illness
  • If the subject is aggressive or hostile:
  • Do not get angry and do not remain alone with him/her
  • Protect the subject from him/herself while protecting yourself
  • Generally speaking, tranquillizers should not be used because they may increase confusion and anxiety, and aggravate prevailing delusions

Back to top