Caffeine

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Caffeine
Drugs and Our Society
CJUS/HPE 151
Part 15
Popularity
1.
Most frequently used stimulant
- most popular
- foods / beverages consumed
- average daily intake: 2 cups coffee (200 mg)
- 30%: 500 mgs or more daily
a. Most common sources:
- coffee bean / tea plants / kola nuts / mate
leaves / guarana paste / yoco bark
b. Coffee drinking throughout history
Popularity
- early 1820s: active stimulant identified
- French / German scientists
- extracted from green coffee beans
- substance with alkaloid properties
b. 40 / 60 years later: identified in several other
plants
- stimulate effect found desirable
2.
Chemical Nature
- group of drugs similar chemically
Properties, cont.
- Xanthines
- theobromine (1842): cacao bean
- theophylline (1888): tea leaves
c. Unique pharmacological properties
- most potent CNS stimulant
3.
Beverages containing caffeine
- unique role in US society
- most common source: unfermented beverages
Beverages
a. Coffee
- derived from coffea plants
- Coffea Arabica: shrub / small tree
- 3 to 5 feet (wild)
- South America / East Africa
(1) Ethiopian prince “Kaffa”
- Ethiopia to Arabia
- important in Arabian civilization
- writings of 900 AD
Beverages, cont.
(2) Reached Europe through Turkey
- medicine
- 1650s: coffee houses England / France
- relax / talk / learn news
(3) Consumed by English colonists
- tea preferred / replaced by coffee
- symbol of English repression
- political expression rather than taste
(4) Movement west: popularity grew
Beverages, cont.
- daily intake peaked in 1986
- consumption: 10 lbs. per person
(5) Side effects:
- attributed to decline
- sleeplessness / heart disease / etc.
(6) American lifestyles
- plays major role
- considered America’s drink
Beverages, cont.
b. Tea
- Camellia sinensis plant
- China / India / Burma / Thailand / Viet Nam
- caffeine / theophylline
- earliest use unknown
(1) Emperor Shen Nung (273 BC)
- first reliable account: medicinal plant
- Chinese manuscript: 350 AD
Beverages, cont.
(3) Use grew slowly
- Dutch brought to Europe (1610)
- adopted by British / integral part
- major economy / colonize India
(4) Dutch (1650) introduced to America
- New Amsterdam
- British: exclusive rights to sell
- high taxes levied
- symbol of ‘British rule’
Beverages, cont.
c. Soft drinks
- 2nd most common source
- 12 ounce serving: 30 / 60 mgs
(1) Consumed by children / teenagers
- others: soda replaces coffee
(2) Added to juices / water
- alluring names
- Surge / Jolt / Aqua Buzz / Krank H2O
Beverages, cont.
- targets young consumers
4.
Social consequences
- consuming caffeine-based beverages
a. Impossible to accurately assess
- both subtle / non-subtle
- stimulant effects = some social influence
b. Integrated into social customs / ceremonies
Social Consequences, cont.
- traditional drinks
c. Consumed with ritualistic devotion
- morning
- meals (or after)
- “interludes” throughout day
- coffee breaks / tea times
d. Popularity: stimulant action
- “jump start” effect
- avoid withdrawal
Other Natural Caffeine Sources
5.
Coffee / tea most common
- other sources popular in rest of world
- guarana: Brazil
- mate: Argentina / Brazil / Paraguay
- kola nut: West Africa/ West Indies/ So. America
a. Chocolate
- contains small amounts
- principle stimulant: alkaloid theobromine
- theobroma cacao tree
- Aztec: “fruit of the gods”
Sources, cont.
b. High esteem: fruit / seed pods
- medium of exchange
c. Mayan Indians: warm drink from beans
- chocolatl: warm drink
- thick / unsweetened / ate with spoon
d. Hernando Cortes: chocolate to Spain
- Dutch (1828): chocolate powder / cocoa
e. Over-the-counter drugs
Physiological Effects
6.
Significant influence
- minor / short-term effects
- high doses / medical problems = dangerous
a. CNS effects
- most potent: caffeine
- followed by: theophylline
- theobromine: little influence
b. CNS responses vary considerably
Physiological, cont.
- 100/200 mgs: enhance alertness / arousal
/ diminishes fatigue
- block drowsiness / facilitate mental activity
c. Stimulates formation of thoughts
- does not improve learning ability
d. More pronounced: un-stimulated / drowsy
- diminishes sense of boredom
- compensate for tedium
Physiological, cont.
7.
Xanthine drinks popular: stimulate effects
a. Adverse effects (greater than 300 mgs)
- insomnia / tension / anxiety / muscle twitches
b. Over 500 mgs: dysphoric feelings
- panic sensation / chills / nausea / clumsiness
c. Extremely high: 5 - 10 grams (1 = 1000 mgs)
- seizures / respiratory failure / death
Physiological, cont.
8.
Cardiovascular / respiratory effects
- stimulate brain / stimulate cardio system
a. Tolerance can occur
- low doses: may increase / decrease
- higher doses: contraction of heart increases
9.
Caffeine intoxication
- high dose: physiological/psychological problems
- caffeinism (10% of adults)
Intoxication, cont.
a. American Psychiatric Association
- caffeine intoxication of CNS
- “psychoactive substance-induced
psychiatric disorder”
b. Essential features:
- restlessness / nervousness / excitement /
insomnia / flushed face / diuresis / muscle
twitching / rambling thoughts – speech /
heart arrhythmia / motor agitation
Intoxication, cont.
- higher doses: ringing in ears / seeing
flashes of light
c. Medical profession:
- large quantities: cancer of kidneys / bladder
/ ovaries / colon
- fetus problems in pregnant women
10.
Caffeine dependence: limited
- most: relatively minor
Dependence, cont.
a. 50% consume 1 to 3 cups: headaches
b. 10%: significantly depressed / anxious /
fatigued without coffee
c. Some experience withdrawal every morning
- before first cup of coffee
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