Psychology 335 - Caffeine and Cannabis Notes

Psychology 335 - Caffeine and Methylxanthines

Discriminative Stimulus Properties

  • Generalization to Cocaine:

    • Some findings show an ability for caffeine to generalize stimulus properties to cocaine, especially observed at low doses.
    • Dopamine (DA) blockers can hinder the discrimination of low doses of caffeine in experiments.

  • Look-alike Drugs:

    • Caffeine and ephedrine are identified as substances that evoke similar subjective effects in naive users.

Subjective Effects

  • Feelings Induced by Low Doses of Caffeine:

    • Well-being
    • Alertness
    • Increased energy
    • Motivation to work
    • Enhanced self-confidence
    • Subjective effects primarily experienced at lower doses.

  • At High Doses (IV Administration):

    • Caffeine may be mistaken for cocaine due to heightened subjective effects and stimulation.

Tolerance and Withdrawal

  • Tolerance Development:

    • Chronic consumption of caffeine leads to an increase in the generation of adenosine receptors, impacting the user’s response.
    • The typical dose-response curve can shift up to six times with chronic exposure.
    • Users typically develop tolerance to subjective effects within a span of four days.

  • Withdrawal Effects:

    • Withdrawal symptoms can include a decrease in locomotor activity, manifested in behavioral changes after cessation.
    • Typical onset of withdrawal symptoms ranges from 12 to 28 hours post cessation and may last 2 to 9 days.
    • Symptoms include headaches, drowsiness, and decreased energy levels.
    • Often, this withdrawal can be mistakenly attributed to general malaise, especially during schedule changes (e.g., holidays).

Studies on Withdrawal

  • Caffeine Withdrawal Study:
    • The frequency of reported headaches and subjective scores on an “energy/active” scale during a 24-day regimen was monitored.
    • Subjects consumed 100 mg of caffeine capsules before switching to placebo then back to caffeine, illustrating observable withdrawal effects.

Self-Administration in Humans

  • Reinforcing Properties of Caffeine:

    • Regular consumers (particularly coffee drinkers) demonstrate a preference for caffeinated coffee and capsules mainly to avoid withdrawal symptoms.

  • Caffeine Dependence Syndrome:

    • Marked by tolerance, withdrawal, a desire to quit, and use despite health problems.

  • Population Studies Findings:

    • Caffeine listed as the most consumed psychoactive substance globally after oil.
    • Average world caffeine consumption is about 70 mg per person per day, primarily sourced from coffee and tea.
    • In North America, average consumption exceeds 200 mg per person per day.

Harmful Effects of Caffeine

  • Reproductive Effects:

    • Studies suggest caffeine can reduce blood flow to the fetus, resulting in lower birth rates and adverse effects during breastfeeding.

  • Cardiac Disease Risks:

    • There is an increase in blood pressure, though it remains debated whether caffeine may directly cause heart disease.

  • Anxiety Disorders:

    • Increased caffeine consumption may contribute to the prevalence of panic disorders and anxiety-related conditions.

Cancer Related to Caffeine

  • Cancer Risks:
    • The relationship between caffeine consumption and cancer is uncertain, dependent largely on duration and dose of consumption.

Behavior and Toxicity

  • Caffeinism:
    • Caffeine-induced symptoms might include anxiety-related issues, which can even appear in the context of social situations such as stage fright.
    • Lethal doses of caffeine are reported to be between 3 to 8 grams, equating to approximately 30 to 80 cups of coffee, and can result in convulsions and respiratory collapse.

Cannabinoids

Endocannabinoids

  • Naturally Occurring Cannabinoids:
    • Found within the body, include anandamide and 2-AG.

Phytocannabinoids

  • Plant-derived Cannabinoids:
    • Notable examples include THC (Tetrahydrocannabinol) and CBD (Cannabidiol).

Synthetic Cannabinoids

  • Man-made Cannabinoids:
    • Include products such as K2 and Spice.

Historical Context of Cannabis Use

History in China

  • Early Reference:
    • Shen-Nung (circa 2700 B.C.) noted the uses of cannabis.

History in India

  • Cultural Significance:
    • Ganja and Bhang celebrated as sources of joy as per The Vedas, described as compassionate gifts to humans.

History in Europe

  • Medical Introduction by William Brooke O'Shaughnessy:
    • Introduced cannabis for medical use in Europe in 1841, following observations in India.

History of Cannabis Prohibition

  • Dangers Associated with Cannabis:
    • Harry Anslinger’s views in 1937 labelled cannabis leading to insanity and destruction of mental faculties.

Cannabis in Canada

  • Early Figures like Emily Murphy:
    • Advocated against cannabis use, promoting harmful narratives.

Recent Developments

  • Canadian Medical Cannabis Regulation:
    • Parker (2000) indicated a constitutional right to access cannabis for medicinal purposes.
    • The Marihuana Medical Access Regulations (MMAR) initiated in 2001 followed by MMPR regulations in 2014, allowing licensed production and enhanced quality control in medicinal cannabis.

The Cannabis Act (C-45) Legislative Framework

  • Key Points of the Act:
    • Sale regulated at the provincial level either through mail or retail.
    • Set minimum age of use at 18, with adults allowed to possess up to 30 grams and cultivate up to 4 plants per household.
    • Legal consequences outlined for providing cannabis to minors, advertising limits, and other penalties.

Cannabinoids Spectrum

Delta-9-tetrahydrocannabinol (∆9-THC)

  • Potency Ranges:
    • Typically between 5-25%, leading to discussions around the rise of so-called 'superweed'.

Cannabidiol (CBD) and Others

  • Cannabinoid Variety:
    • Over 100 cannabinoids identified with potential therapeutic effects varying from anti-epileptic, analgesic, antipsychotic, and anti-inflammatory properties.

Cannabinoids and Terpenes

  • Entourage Effect:
    • Whole plant synergy considered as a factor in cannabis effects, leading to potential enhanced efficacy of combined cannabinoid and terpenoid interactions.

CBD's Mechanism of Action

  • Interaction With Receptors:
    • CBD doesn’t activate CB1 or CB2 receptors directly but interacts indirectly through various pathways (e.g., as an agonist for 5-HT1A and adenosine).

Effects of Cannabis Use

Subjective Effects on Behavior and Mood

  • Bipolar and Contradictory Effects:
    • Cannabis use is reported to generate varied changes in mood, perception, and the perception of time.

Cognitive Effects and Memory

  • Impact on Memory Retrieval:
    • No significant effects on previously learned material, though short-term memory retrieval and focus may be hindered during use.

Therapeutic Potential of Cannabis

Medical Use Statistics

  • Lorem Ipsum:
    • Significant user groups report utilizing cannabis primarily for pain management (acute and chronic), mental disorders (such as anxiety and depression), insomnia, and other clinical indications.

Access Issues and Legislation Effects

  • Patient Surveys:
    • Findings indicate decreased use of opioids and benzodiazepines post-implementation of medical marijuana laws, indicating a trend towards cannabis being seen as a substitute for these substances.

Mental Health Corner**

  • Therapeutic Use Findings:
    • Cannabis has been linked with reductions in anxiety and improvement in sleep conditions among patients at various physiological and psychological levels.

Clinical concerns and research

Cannabis and Psychosis:**

  • Risk Associations:
    • United literature indicates differing prevalence rates of psychotic disorders among cannabis users and early onset risk associated with heavy use.

Considerations in Cannabis Research:

  • Longitudinal studies suggest that while cannabis may contribute to psycho-social problems, multifactorial dimensions must be considered beyond the simplistic cannabis usage-perspective.