chapter 20 - psychoactive plants

Question 1

What are the most widely used psychoactive substances used in the US?

Answer 1

• ## caffeine, alcohol, and nicotine

Question 2

What were the most widely used psychoactive drugs in 1995?

Answer 2

• marijuana, cocaine, and heroin
• 50% of population has used
• 15% of population has used in the past year

Question 3

How much money was spent in 1990 on psychoactive substances?

Answer 3

• $50B on alcohol
• $40B on cocaine
• $35B on tobacco
• $25B on marijuana

Question 4

Psychoactive plants

Answer 4

• 6000 years ago, on Sumerian clay tablets it read: opium, “joy plant”

Question 5

Psychoactive drug effects depend on:

Answer 5

• pharmacology of drug
• biology of the individual
• psychology of individual
• cultural setting

Question 6

Pharmacology of psychoactive substances

Answer 6

“If the human brain were simple enough for us to understand, we would be too simple to understand it” - the developer of Prozac

Question 7

CNS

Answer 7

• network of nerve cells (neurons) in the brain and spinal cord
• neurons release NT where their ends meet at synapses
• some NT inhibitory and others are excitatory

Question 8

Psychoactive drugs

Answer 8

• mimicking, amplifying or block the effects of NTs
• stimulants, depressants, or hallucinogens
• mostly alkaloids (THC is a phenolic)
• narcotic: technically a depressant, but now used as any ‘dangerously addictive’ psychoactive compound

Question 9

Dopamine

Answer 9

• one of the 100s NTS
• primary component of the “reward circuit”
• dopamine receptors mainly affected by psychoactive drugs

Question 10

Effects of psychoactive drugs on dopamine release

Answer 10

• increase dopamine levels in nucleus accumbens
• cocaine blocks return of dopamine to Ventral Tegmental area: blooks negative feedback loop resulting in increased levels of dopamine
• Opiates inhibit shutdown of dopamine production

Question 11

What effect does chronically elevated levels of dopamine have?

Answer 11

• chronically elevated dopamine leads to inhibition of dopamine production in Ventral Tegmental Area
• this ‘tolerance’ can lead to the need for increased drug use
• people search for the first high feeling

Question 12

What are some examples of depressant psychoactive drugs?

Answer 12

• Opium Poppy and other opiates
• Heroin
• Kava
• alcohol

Question 13

Opium poppy (Papaver sominiferum)

Answer 13

• milky latex rich alkaloids that are CNS depressants
• native to Middle East
• poppy also grown for seed

Question 14

Opium wars

Answer 14

• Chinese wanted payment in silver from British for tea, silk, and porcelain
• British and US ships smuggle opium from India to China; China destroys opium
• Britain retaliates with 1st and 2nd war
• creates addictive culture that ends with communist revolution

Question 15

Opium alkaloids

Answer 15

• includes morphine (main drug for intense pain) and codeine
• provides euphoric sensation, respiratory depressant

Question 16

Semisynthetic and synthetic depressant examples

Answer 16

semisynthetic: heroin, oxycodone, and hydrocodone
synthetic: fentanyl

Question 16

Heroin

Answer 16

• semisynthetic chemical modification of morphine, and much more addictive
• now illegal in US but produced legally in India

Question 17

Kava (Piper methysticum)

Answer 17

• CNS depressant
• root made into social, sacred, and medicinal beverage of South Pacific
• liver toxicity link found in US and Europe (FDA banned)

Question 18

Alcohol

Answer 18

• CNS depressant
• small molecule that is easily carried from blood to brain
• may affect many NT systems
• affects balance by affecting ear gel

Question 19

What are some examples of hallucinogenic psychoactive drugs?

Answer 19

• marijuana
• Peyote
• Nightshade family (Solanaceae)

Question 20

Marijuana (Cannabis sativa)

Answer 20

• one of the oldest cultivated plants: medicine, fiber, oil, and seed
• resin source of THC
• found around the world, but may have originated in central Asia
• medicinally used in China 5 thousand years ago
• one of five sacred plants in India

Question 21

What is the principle psychoactive compound in marijuana?

Answer 21

• THC (prescription drug Marinol)
• also has other cannabinoids
• THC content varies between species and varieties of Cannabis, sexes, growing environment, and plant parts
• pure resin = hashish

Question 22

Effects of THC on the CNS

Answer 22

• THC binds several cannabinoid receptors on the CNS
• THC mimics anandamide and endocannabinoids naturally produced in the body

Question 23

Medical marijuana medical uses

Answer 23

• reducing nausea during chemotherapy
• lowering intraocular pressure for treatment of glaucoma
• reducing muscle spasm in MS
• Parkinson’s and spinal cord injury patients

Question 24

What is the legal status of marijuana?

Answer 24

- federally classified as illegal substance - FDA still advises against medical use

Question 25

Peyote

Answer 25

- contains various alkaloids - comes from the cactus Lophophora willamsii, used by indigenous peoples of now SW USA and NW Mexico for 3k years - North American church use occurs but supreme court upheld state's right to outlaw

Question 26

Nightshade Family (Solanaceae)

Answer 26

- include deadly nightshade (Atropa belladonna), henbane, Jimsonweed, mandrake - part of potions used by witches and sorcerers in Middle Ages - atropine from henbane: antispasmodic, heart stimulant, bronchodilator

Question 27

What are some examples of stimulating psychoactive drugs?

Answer 27

- Coca (Erythroxylum coca) - Cocaine and Crack - Tobacoo -

Question 28

Coca (Erythroxylum coca)

Answer 28

- cocaine alkaloid extracted from coca plants from Andes mountains of South America for over 3k years - sacred plant to the Incas

Question 29

Cocaine use and Crack

Answer 29

- powerful stimulant leading to short euphoria - local anesthetic similar to synthetic Novocain - highly addictive and can lead to sudden death - Crack: purified cocaine by boiling in ether - crack was rocky and had worse legal consequences if caught - cocaine was powder with less serious consequences-

Question 30

Tobacco (Nicotiana spp.)

Answer 30

- Solanaceae family, native to New World - cultivated for 5k years - nicotine: major addictive alkaloid - world-wide: 1.1 billion smokers - 18% of world population uses

Question 31

Tobacco and health

Answer 31

- 1948 JAMA: no evidence to abolish tobacco use - 90% of lung cancers due to tobacco smoking: leading preventable cause of death - chewing tobacco 50x greater oral cancer risk - addiction may occur after first few cigarettes

Question 32

Does clinical research support the banning of smoking tobacco?

Answer 32

- California first state to enact statewide smoking ban - 2009: Nebraska clean indoor air act bans smoking in enclosed workplaces including bars/restaurants - clinical research DOES support ban due to effects of secondhand smoke

Question 33

Costs of substance abuse?

Answer 33

- abuse of tobacco, alcohol, and illicit drugs is costly to our nation - exacting over $600 B annually in costs related to crime, lost work productivity and healthcare

Question 34

Portugal legalities

Answer 34

- 2001 decriminalized possession of amounts equal to a 10-day supply of all drugs including cocaine and heroin - possession of small amounts still legal, but penalty similar to a parking violation - Portugal has enhanced drug-treatment programs - "drug users aren't criminals, they're sick" - head of Portugal anti-drug program

Question 35

Effects of drug decriminalized drugs in Portugal

Answer 35

- since 2001, drug usage rates remained roughly the same - drug-related pathologies like STDs and death from overdose have declined dramatically - "Portuguese decriminalization framework has been a resounding success" - Report from CATO Insititute