Nicotine UNCW Faculty and Staff

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					Nicotine
Chapter 7
History of Tobacco
History of Tobacco &
  Nicotine
• Smoking practiced
  among the early Mayas,
  probably in the district
  of Tabasco, Mexico, as
  part of their religious
  ceremonies 86-161 AD
• Europeans’ first
  exposure from
  Columbus 1492.
  Exposure was not
  widespread. Tobacco
  was not well thought of
  at first
History of Tobacco
1560 - Marked as 1st
  yr tobacco officially
  introduced to
  Europe
Proponents of tobacco
• Sir Francis Drake
• Sir Walter Raleigh
  – Led to the
    fashionability of pipe
    smoking of tobacco
History of Tobacco
King James I of England
• 1604 - Pamphlet condemning tobacco
  – “bewitching of tobacco”

Early 1700s Russia
  – “Westernization” of people
  – penalties for smoking (torture, Siberian exile,
    death)
 History of Tobacco

By 17th century
• Tobacco here to stay
  – In Western Europe, used as treatment for
    migraines
  – Japan & China stop enforcing prohibition of use
  – Russia opens door to West
  – Sultan of Turkey begins to smoke
          History of Tobacco
• 1828 - Nicotine was isolated
• Cigarettes first appeared in 1850s, but
  chewing still more popular
 Tobacco & Nicotine In US

• In U.S., tobacco became major commodity
  in early 1600s, used as currency
• Financed Revolutionary War
  – Ben Franklin promised Virginia's tobacco to
    France
  – Had it not been for tobacco, no French
    assistance & no USA
  Tobacco Use in 20th Century
Future favored cigarettes over other usage
• New emphasis on social manners
• Public health issues of infectious disease
  – decrease in chewing except in small rural towns of U.S.
• Women began smoking
  – But, 1904 NYC woman arrested for smoking in public
• 1920s - “reach for a Lucky instead of a sweet”
  – Promoted weight loss effects
• Also cigarettes in WWI
  Tobacco & Nicotine In US
• 1890s - no medicinal value for nicotine
  – dropped from U.S. pharmacopia
• 1925 - 14 states banned smoking
• 1938 - study linking cigarettes & lung cancer
• 1954 - more stats relating smoking to lung cancer
  & cardiovascular disease
• 1964 - first Surgeon General's report
  – advised smoking shortens life expectancy
• 1986 - Surgeon General's report on passive
  smoking
• Use continued to decline over past twenty years
• 2000 – Worldwide consumption still on increase
Nicotine Forms
• Tobacco
  – Smokeable
    • Cigarette
    • Pipe
    • Cigar
  – Leaf (Chewing)
  – Leaf (Dip)
  – Snuff (powdered)
• Transdermal Patch
Snuff
• Grind tobacco into fine powder
• Pinch into nose & exhale with sneeze
  (cleared head of “superfluous humours”)
• 1700s – snuff overtook smoking as
  method of choice
  – Started in France & spread through rest of
    Europe
  Chewing
In U.S., snuffing replaced by chewing
• Freed hands for working
• Low cost - democratic custom all could have
• “spitting” seen as nasty habit, also health
  issue
  – Major cause of spread of infectious disease (TB)
Cigar Smoking

• Tight rolls of tobacco leaves
• Flue-curing - process of heating tobacco
  leaves
  – to cure them, makes milder smoke
• Also new type of leaf
  – North Carolina #1 tobacco-growing center
• Mixed effects of chewing with ingestion of
  smoke
   Cigarettes
• Rolls of shredded tobacco wrapped in paper
• 1614 – Invented by beggars in Seville, Spain
  from scrap of cigars
• 1856 - Became popular with English soldiers in
  Crimean War - Spread throughout Europe
  U.S, not inclined to use it
  – Public image
  – Rumors of opium, arsenic laced paper, & camel dung,
  – Also image:
     cigarette - dainty & “sissy”
     vs. cigars - fat, long & dark
              Cigarettes

1881 - James Bonsack patented cigarette-
  making machine
• Made cigarettes even more low-cost
• Revolutionized tobacco industry
  - From 300 cigarettes per hour by hand
    to 3 machines producing 200 cigarettes
    per minute
            Cigarette Smoking
Nicotine in a cigarette – 8 to 10
 mg
Smoking – delivers about 1-3 mg
 to the smoker
Technique of smoker can increase
 nicotine (time smoke is in lungs, rapid
 puffing)
 Nicotine Pharmacology
• Biphasic action-
  nicotinic acetylcholine
  receptors
   – Agonist – low doses
   – Antagonist – high doses
• Although a stimulant, it
  is often used to relax
• Works in CNS and PNS
• One of the most toxic
  dependence-producing
  psychoactive
  compounds overall
   – Nicotine acts to stimulate
     dopamine release in
     mesolimbic dopamine
     pathway (reward center).
Nicotine Pharmacology

•   One of most powerful poisons ingested
    by Americans
    – LD50 60 mg
•    Can't happen via inhalation
•    Orally, two protections against death
    1. quick first pass metabolism through
       liver
    2. activation of vomiting center
Peripheral Effects
• A sympathomimetic
  – Increases heart rate, blood pressure,
    respiration
• A parasympathomimetic
  – Increases smooth muscle (GI tract) activity
  – Increases HCL production in stomach
Central Effects
• Arousal
• Improves vigilance & rapid information
  processing
• Improves mental performance &
  memory
• Stimulates adrenalin and ADH release
• Nicotine may reverse some deficits
  caused by alcohol
Biotransformation/Excretion
• Broken down by lung and liver
  – >90% in liver
• Metabolization of nicotine and other
  toxins in cigarette smoking lowers blood
  levels of many important drugs.
• Excreted through kidneys (urine)
• Lungs do some excretion
Tolerance
• Develops rapidly
  – Within the first exposure for some effects
     • Area Postrema
  – Can build up and dissipate over the course
    of a day
  – Chronic tolerance happens as well

• Dispositional Tolerance
  – Some smokers clear nicotine faster
Dependence
• One of the most dependence-producing
  drugs
  – Pharmacology – Stimulates reward center
    influences ANS
  – Function – Weight control, coping with
    negative affect/stress, cognitive
    enhancement
  – Social Factors – Friends, habit, context
Withdrawal Symptoms
of Nicotine

•   Lethargy, decreased arousal
•   Constipation
•   Headaches
•   Disrupted sleep cycles
•   Irritability/anxiety
•   Excessive hunger (blood sugar drop)
Compounds in Tobacco
• Tar - sticky substance
  – Amount varies from 12 - 16mg to 6mg
  – Last 3rd of cigarette contains 50% of
    tar (final puffs more hazardous)
  – Prevents cilia from working, decreases
    cilia escalator
  – Increases carcinogens compounds to
    settle on tissue rather than being
    expelled
Compounds in Tobacco
Carbon Monoxide
• Odorless & tasteless, but extremely toxic
• Attaches to hemoglobin
  – Hemoglobin has greater affinity for CO than
    oxygen
     • Accumulation of CO occurs
     • Leads to asphyxiation of body
Health Effects of Nicotine Addiction
• Cardiovascular Disease
  – Most likely killer
• Cancer
  – Approx 90% of all lung cancer
• Chronic Obstructive Pulmonary Disease
  – All long-term smokers get some level of
    COPD
  – Emphysema most serious
Approaches to Treatment

  • Self-help

  • Behavioral intervention

  • Pharmacotherapy

  • Combined strategies
Nicotine Replacement

• Nicotine gum

• Transdermal nicotine

• Nicotine aerosols
Pharmacotherapy

  • Clonidine

  • SSRIs

  • Zyban
Quitting Overall
• Combination of strategies works best
• Behavioral + replacement +
  pharmacotherapy
• Quitting reduces risk of all-cause
  mortality among other diseases
• Risk of lung cancer remains elevated
  but drops significantly