drugs and drug use. what is a drug? drug any substance that alters the chemical reactions...
TRANSCRIPT
What Is A Drug?• Drug any substance that alters the chemical
reactions (homeostasis) of the body1) Medicinal drugs– Help fix illness or deal with symptoms of
illness (pain, mood swings, etc.)– Aspirin, morphine, antibiotics…
2) Recreational drugs– Alter you moods for pleasure/work– Often illegal due to being highly
addictive– Alcohol, nicotine, heroine…
• 3 Types:1) Depressant inhibit nerves2) Stimulant enhance nerves/body3) Hallucinogen alter nerves to cause visions
Why Are Drugs Dangerous?• Formation of addiction:1) First time • effect of drug is very strong and mostly
positive (euphoria)2) Building a habit • drug becomes part of your lifestyle; body
creates tolerance (alter set point) so more drug is needed to get same effect
3) Addiction• body now depended on drug and mood is
horrible when not on drug (dependent)4) Withdrawal symptoms • body slow to reset set point to normal;
negative feelings and sickness drive person back to drug
Good Drugs• Antibiotics chemicals that bind to
bacteria and pathogens– Kill bacteria
• Break homeostasis• Break cell wall/cell membrane
– Stop growth/ mark it for white blood cells
• Produced first time we get sick so the next time our body can kill the pathogen faster
• Medicinal antibiotics help our immune system kill pathogen faster– Narrow-spectrum few species– Broad-spectrum many species
• Why can’t these work on viruses?– Viruses are not cells/not alive
So-So Drugs• All medicinal drugs, if used properly,
can help a person• All mood-altering drugs can become
additive– Depends more on person than drug
• Pain-killers chemicals that slow down impulses and inhibit pain signals so the body does not feel pain– Based on opiates (opium)– Morphine, Aspirin, valium…
• Without pain-killers modern medicine would be very limited– Painful surgeries– Painful recovery after injury
Bad (Legal) Drugs• Drugs with mostly no medical
benefits but are accepted socially/legally
• Alcohol – Ethanol made from fermentation of
glucose– Small molecule; quickly absorbed into
body and spreads through blood– Broken down by enzyme in liver
(alcohol dehydrogenase) • Depressant slows down nerve
impulses– Low: Remove inhibitions– Med: Lose fine motor control, memory
loss, and deep sleep– High: Brain damage, coma, and death
Alcohol and You• Effects of alcohol:
– BAC blood alcohol concentration – 20-50 relaxed– 50-80 euphoria – 80-120 impaired (tipsy)– 120-260 drunk– 260-400 very drunk (blackout)– >400 coma/death (alcohol poisoning)
• Long Term Effects:– Cirrhosis damaged liver can’t
function– Brain/heart damage– Alcoholic dependent on
alcohol/ socially difficult person to deal with
Bad (Legal) Drugs• Nicotine
– Found in tobacco plants (pesticide); inhaled through cigarettes
– Absorbed into blood through alveoli and travel to brain
– Stimulant that raises blood pressure, heart rate, and activates synapse (addictive)
• Cigarettes = Poison– Tar cooled smoke turns into thick
black globs that block gas exchange; cannot be removed by cilia
– Carbon Monoxide (CO) permanently binds to hemoglobin, reducing blood O2 by 10%
– Carcinogens chemical that cause DNA to mutate and become cancer
Don’t Smoke!!• Long Term Effects:1) Bronchitis tar causes extra
mucus in lungs (phlegm); bacteria live happy but make you sick and cough a lot
2) Emphysema alveoli weaken and burst; decreases gas exchange
3) Heart disease CO and lowered gas exchange mean heart pumps harder to more O2; smoke also thickens arteries so might get CHD
4) Lung cancer 90% of lung cancer is those who smoke; carcinogens cause tumors (mass of cells) to spread in lungs
Bad (Legal-ish) Drugs• Marijuana
– Dried leaves of cannabis plants– Inhaled through marijuana
cigarettes and absorbed into blood– Depressant that slows down
synapse transmission• THC inhibit receptors of
hippocampus (brain region)• Effects of Marijuana:
– Short-term memory loss– Slowing of time– Slow coordination – Paranoia– Dry mouth/hunger – Numbness
Is Marijuana Bad?• Long Term Effects:
– Lung tissue damage due to inhaling smoke
– Lowered immune system from THC – Cancer; some carcinogens in
cigarette– Not addictive (body doesn’t depend
on it) but can be an addictive life style
• Negative affects less than alcohol/nicotine, which are legal drugs
• Called “Gateway Drug”; being illegal it may lead to other illegal drugs that do lots of harm
Bad (Totally Illegal) Drugs• Highly addictive mood altering
and hallucination drugs• Heroin– Made from morphine (opiate)– Smoked, injected, sniffed– Inject risks veins collapsing from
tissue damage– Powerful depressant that numbs
pain receptors– Puts set point to low for pain
that not having drug becomes painful AND the body builds a tolerance so more and more heroine is needed
Don’t Do Heroine• Long term effects:
– Constant need for “fix” (more heroine)
– Expensive and illegal drug turns many to crime
– Social outcasts– Tissue damage at inject site– Nausea, hallucinations, and sweating
if drug is absent for too long (withdrawal)
• Rehabilitation:– Giving up heroine “cold turkey” is
almost impossible– Methadone, drug similar to heroin
but less damaging, can be given in shrinking amounts until “clean”
More Bad (Illegal) Drugs• Cocaine:
– Power extract from the Erythroxylum coca bush
– Snorted, injected, or smoked; extremely stimulant that can cause death on the first use
– Floods brain with neurotransmitters leading to happy feelings and a “rush”
• LSD:– Accidently discovered in the 1930’s– Eaten or injected; hallucinogen that causes
euphoria, enhanced colors, and visions• Ecstasy:
– Accidently discovered in 1912– Eaten; hallucinogen that causes euphoria,
enhanced colors, and perception