Lecture 6: Cannabis Flashcards
(28 cards)
Marijuana tax act of 1937
Followed the regulation-by-taxation theme of the 1914 Harrison Act
- Grower, distributor, seller, and buyer were taxed
- Administratively almost impossible to deal in Cannabis
Bureau of Narcotics uniform law specifically names Cannabis sativa
- Current federal and uniform laws refer more generally to the genus Cannabis
State laws made possession and use of Cannabis illegal per se
1969: US Supreme Court declared the Marijuana Tax Act unconstitutional
After the Marijuana Tax Act
Cost of marijuana increased significantly
Reports continued to be published that marijuana use had less serious effects than commonly believed BUT
- Substantial disagreement over the interpretation of research findings
1950s and 1960s
- Little scientific research done on Cannabis
- Use of Cannabis continued to increase; A common symbol of youthful rejection of authority; Identification with a new era of personal freedom
Usage rose around 1980, declined until the mid-1990s, and then peaked in the late 1990s, although never reaching the levels in the 1970s
Cannabis Policy
Legalization- laws or policies which make the possession and use legal under state law
Decriminalization- laws or policies adopted in state and local jurisdictions which reduce the penalties for possession and use from criminal sanctions to fines or civil penalties
Medical- state laws which allow an individual to defend him or herself against criminal charges of possession if the defendant can prove a medial need under state law
Cannabis: The plant
Marijuana is a preparation of leafy material from the Cannabis plant that is smoked
Marijuana is classified separately because its effects are varied and complex
- Sedation
- Pain relief
- Hallucination (in large doses)
Effects it produces in most users are sufficiently different from the effects of depressants, narcotics, and hallucinogens to merit its separate classification
Cannabis
Cannabis is a genus of plants (marijuana)
- Examples: Cannabis sativa, cannabis indica
Fibrous plant with practical uses (hemp)
Tetrahydrocannabinol (THC) concentration varies across plants and across components of plants
Potency (from least to most):
- Roots
- Stem
- Seeds
- Leaves
- Buds
Is marijuana addictive?
Yes, can be addicting
- Can show symptoms of dependence
- Can show symptoms of withdrawal; withdrawal is short
- Cause/effect with co-occurring mood disorders unclear
- Not as addictive as alcohol or cocaine
Pharmacology: Cannabinoid Chemicals
Chemistry of Cannabis is complex and unique
- Active agent contains no nitrogen and thus is not an alkaloid like other psychoactive plant materials
Cannabinoids are 66 chemicals unique to the Cannabis plant
- Delta-9-tetra…(THC); Isolated and synthesized in 1964; The most pharmacologically active cannaboid
- There may be several other active agents in Cannabis
Potency
Average potency (THC content) of pot has more than tripled in the past two decades
Avg. potency jumped from 3.4% THC in 1993 to 12.3% THC in 2012
- Labs have seen as high as 36%
Many retail shops and medical dispensaries across the US have strains ranging from 25% to 28%
Cannabis Sativa
§Originated in Asia, but now grown
worldwide
§Grown primarily for its fibers, from
which hemp rope is made
§Grows as a weed in the U.S. and Canada
§A lanky plant up to 18 feet high
Cannabis indica and ruderalis
Indica §Grown for its psychoactive resins §Cultivated in many areas of the world §A compact plant 2 to 3 feet high §Potency varies depending on plant genetics and environmental conditions
Ruderalis
- Grown primarily in Russia
Cannabis
§Marijuana: schedule 1 controlled
substance
§32 states and DC allow medical cannabis
§10 states and DC allow legal
recreational use
§2012: First legalized recreational use
[Ways of ingesting] Cannabis Resin
Primary psychoactive agent in
Cannabis is delta-9- tetrahydrocannabinol (THC)
THC is concentrated in the resin, most of which is in the flowering tops
§Less in the leaves
§Little in fibrous stalks
Psychoactive potency of
Cannabis preparations depends on the amount of resin present
[Ways of ingesting] Hashish
Consists of pure resin that has been carefully removed from the surface of leaves and stems §May be less pure depending on how carefully the resin has been separated from the plant material
Rare in the U.S.
Hash oil
§More efficient production than typical hash
§Involves boiling the plants in alcohol and evaporating the resulting liquid down to thick, dark hash oil
§Potency of hash oil varies but can contain more than 50 percent THC
Mechanism of action
Cannabinoid receptor family reactive to THC
Concentrated in: §The reward pathway §Areas responsible for motivation § Integration of sensory experiences §Motor coordination
Endogenous cannabinoids
§Example, anandamide
Pharmacology
Smoked cannabis
§ THC is absorbed rapidly by the blood and travels to the brain and then the rest of the body
§ Within 30 minutes, most THC is gone from the brain
§ Peak psychological and
cardiovascular effects occur
together within 5 to 10 minutes
Oral THC § THC is absorbed more slowly and the liver transforms it into 11-hydroxy-delta-9-THC § Less THC reaches the brain §Peak effects occur about 90 minutes following ingestion
Metabolites have different half–lives § After one week, 25 to 30 percent of the THC and its metabolites might remain in the body § Two or three weeks may be required to completely eliminate a large dose of THC and its metabolites
High lipid solubility of THC and its metabolites
§ Selectively taken up and stored in fatty tissue, to be
released slowly
§ Differing effects for biological sexes
§ No easy way to monitor THC and metabolite levels and
relate them to effects
§ Long-lasting low concentrations of THC and metabolites
have effects on the brain and other organs that have not
yet been determined
Physiological Effects
Cardiovascular effects
§ Increased heart rate occurs after smoking marijuana
and ingesting oral THC; Time course differs substantially following the two different
methods of administration
§ Research findings on the effects of cannabinoids on blood pressure have been mixed
§ Cardiovascular risks of marijuana use have not been
shown in young, healthy users; People with cardiovascular disease should probably avoid
marijuana and oral THC due to effects on heart rate
What marijuana does to your brain
THC is the psychoactive component • Structural changes happen in the brain (volume, shape, and density of grey matter) • Nucleus accumbens and amygdala (PLEASURE/REWARD circuit)
What are behavioral effects
Learning, coordination, problem solving, motivation can be affected • Can have long-term effects • Heavy use prior to age 18 can have long term effects on motivational system (dopamine)
Medical uses
Appetite stimulation, enhanced food appeal § Addresses side effects of chemotherapy (cancer) and antiretroviral therapy (HIV)
§Chronic pain, neural pain
Seizures
Medical marijuana as helpful as we think?
• Does not prevent cancer
• Regarding breast and brain cancer, certain compounds in marijuana can
stop or lessen the SPREAD of the cells of the disease
• Cannabinoids are the compounds that help, though with so many of them, it’s difficult to determine which one(s) are involved
• Can help with sleep, increase appetite,
help mediate chronic pain (not
headaches or minor pains)
• Many conflicting studies
Risks of long term use
Some evidence of respiratory
system effects
§ High level of exposure § More years and heavier use
associated with lung diseases
§ Bronchitis
§ Chronic obstructive pulmonary disease (COPD)
Tobaccos smoke vs. marijuana smoke
• Many tobacco smokers die of heart disease, not just cancer
• Not healthier, smoke is
smoke, regardless of
psychoactive substances
• essentially, body is increasingly stressed by the other non-psychoactive compounds in the smoke that’s directly affecting cardiovascular health
Smoking vs. vaping
Combustion process (smoking) deliver it directly into blood stream through lungs
Vaping uses much lower heat
• Still new, so unclear what long term effects
are
• Widely considered to be better for you than
smoking because you don’t have the irritant
of smoking
• Inhale fewer toxic compounds and less
carbon monoxide
• Can be way more potent, so dosing can be
difficult/dangerous; Have shown greater risk of withdrawal
