Download Drugs - IVCC

drugs
Controversy, danger, tradition
Controversy and
confusion
• Uneasy boundary between legal and
illegal, beneficial and harmful
• Many legal drugs injure in high amounts
• Many are addictive
• Many illegal drugs have medical uses
• Gateway drugs?
• Misinformation – often causes people to
ignore real risks
background
• Humans use, and abuse, a wide variety of
drugs which exert widely ranging effects
• Genetics play a role in our differing
sensitivities to drugs
• Also, behavioral tendencies like
impulsivity, novelty-seeking, hyperactivity,
and variations in tolerance of stress, are
important
Focus on the brain
• The release of dopamine and the
pleasure which follows, tells us what we
like
• This nudges us into eating, drinking, and
other beneficial behaviors
• Years of research has revealed that
ingesting many drugs also causes
dopamine to be released, hi-jacking this
natural reward system - to our peril
Underlying
neurology
• The dopamine circuit begins in the ventral
tegmental area (found at the top of the brain
stem) which synthesizes dopamine which it
passes to the
• Nucleus accumbens which then connects
through its axons to areas of the frontal lobes
• Continued use of some drugs (opiates) causes
neurons to shrink or otherwise work less
effectively, forcing the user to rely on the drug for
pleasure
but there is more
• Two other key brain structures are also
involved
• The amygdala adds an emotional overtone
to the desire for this manipulation of the
reward circuit
• Even more importantly, the hippocampus
makes sure that we remember the fun
times associated with the drug, and the
surroundings which accompany it
perspectives
• Many drugs decrease our ability to
experience pleasure normally
• We then need them to make-up for what
they have taken from us
• But these changes to our natural reward
system can also be effected by other
things such as gambling, video games,
even sweets
alcohol
• World-wide and ancient use
• Part of many of our customs and traditions
• At the most basic level, simply a class of
molecules
• We are concerned with ethanol – the type
which people drink
Alcohol – the
depressant that
makes us act out
• While we typically link drinking alcohol
with wild, reckless behavior, it is actually
a depressant
• That’s because it, especially in high
amounts, lessens our inhibitions by
turning off our frontal lobes, increasing
impulsivity/risk- taking behavior
• Excessive use leads to physical damage
tranquilizers
• Another type of depressant
• Help us relax, fall asleep and decrease
muscle tension
• Barbiturates formerly commonly
prescribed, now out of favor – addiction
and other risks
• Benzodiazepines, such as valium, now
hold sway – less addictive
bennies
• Great danger mixing them with alcohol
• Both stimulate production of the neurotransmitter
GABA, which can inhibit the function of the
medulla disrupting our breathing and heartbeat –
a truly fatal mix
• Another aspect of these drugs is their use as
“date rape” drugs – very inconspicuous
• Flunitrazepam/Rohypnol, or “roofies”
• Induce euphoria, lack of inhibitions, amnesia
narcotics
• Produce drowsiness, insensitivity to pain
and indifference to events
• Most commonly opiates
• Natural substances derived from the
opium poppy
• Also synthetic compounds with similar
chemical structures - methadone
Opiates - why they
wreak such havoc
• Give users a warm, happy, contented
feeling
• Heroin, morphine, methadone (synthetic)
• Virtually eliminate pain and anxiety but at
the cost of apathy and fast addiction
• When the unnatural production of
dopamine ceases the body cries out for it
• If denied, chemical withdrawal begins
Withdrawal from
opiates
• During withdrawal all of the pleasant
effects of the drug are reversed
• While before there was contentment now
there is anxiety, before happiness now
pain
• Worse yet, we need more - tolerance
• Need for a “fix” causes desperate actions
• theft, burglary, prostitution, shattered
lives, criminal prosecution
Long term effects
• Longitudinal studies paint a very bleak
picture
• Of 581 users followed from 1962, nearly
half were dead by 1997
• Survivors self-medicated, including
cigarettes (67%)
• They also faced many health problems,
including hypertension, liver and lung ills,
etc.
stimulants
• Drugs which boost energy, alertness,
activity and pleasant feelings
• Caffeine perhaps the most widely used
drug? – 90%!
• Delivered through coffee, chocolate, soda,
energy drinks, tea
• Can lead to dependency – headaches and
drowsiness if denied
cocaine
• The drug of choice in the 80’s and beyond
• Derived from the leaves of the coca plant
• Creates a euphoric sense of happiness
and increased activity
• Considered a stimulant because it turns off
inhibitors, leading to an increase in
behaviors
• But its use decreases over-all brain activity
More cocaine
• Very powerful, with many effects
• Works by preventing a terminal button’s
synaptic vesicles from reabsorbing
dopamine (reuptake) thus increasing its
effects
• Also, kicks up norepinephrine and
serotonin levels
• Works as an anesthetic ( as does
lidocaine and Novocain) by stopping
action potentials
Cocaine and
addiction
• Usually taken in powder form with
euphoria coming on within minutes and
lasting for up to an hour
• If smoked through free basing, its effects
emerge even faster
• The faster the pleasure, the quicker the
addiction
Crack – addiction
squared
• Crack cocaine, first developed in the mid80’s, provides even quicker, virtually
instantaneous, pleasure
• Addictive after only a few uses
• Very expensive, readily addictive and
quick to lose its effects
• It takes over lives, ruining careers and
families
Long term
• While coke-triggered heart attacks and
strokes strike occasionally, its residual
damage is harder to assess
• Many who started to use it in the 80’s are
now well into their 50’s and the number of
addicts over 50 is set to explode, perhaps
to over 4 million
• Effects are often worsened by overall
neglect
marijuana
• CONTROVERSY
• Intensifies sensory experiences, induces
euphoria, distorts time perception, also
can lead to feelings of anxiety
• Formally known as Cannabis sativa
• Main psychoactive chemical is called THC
• Cultivated for at least 3000 years
The neurochemistry
of marijuana
• Mimics a neurotransmitter called
anandamide
• They attach to receptors which affect short
term memory (on the hippocampus) which
can make it difficult to remember events
and learn
• Also they impact our muscle coordination
by altering the normal functions of the
cerebellum
Medical benefits
• Research shows that marijuana aids some
medical conditions:
Chemotherapy problems – decreases
vomiting, nausea, and anxiety
Aids-related wasting – improves appetite
Pain and muscle spasms – decreases
these plus depression
Glaucoma – decreases pressure on eye
Why pot?
• It is so easy to administer
• Puff by puff, the user can simply stop
when acceptable levels have been
reached
• Low toxicity
• Plus, its effects last no longer than 2 – 3
hours and no chance of overdose
• But, since it is fat soluble, it can be
detected for 28-30 days after ingestion
The debate
•
•
•
•
Life threatening?
Harmless?
Probably neither.
A gateway drug? (millions spent)
very few move on to cocaine or heroin
most used tobacco and alcohol first
if marijuana disappeared would cocaine
and heroin?
withdrawal
• Is pot addictive?
tolerance doesn’t seem to develop
nothing compared to opiates, alcohol, or
nicotine
very little proof of any residual effects
99% discontinue use without any
withdrawal effects
A real danger?
• Amotivational syndrome
• Putting off important things till tomorrow
because you got high today
• Coupled with well established barriers to
learning, pot smoking can cause people to
waste a lot of time and money
• Fact of fiction?
Long term
• A 2003 study stated that even among
regular users there is no proof of
irreversible cognitive damage
• Uncertain as to long range pulmonary
disease and cancers though pot does
contain carcinogens
hallucinogens
• Drugs which induce sensory distortions
• Can come from plants – mushrooms
(psilocybin) or cactus (peyote)
• Also produced synthetically – LSD
• Famous for amazing intensification of
sensations and experiences – from dreamlike states to transcendent mystical events
Mescaline and
psilocybin
• Mescaline, better known as peyote, is
derived from a Chihuahan cactus found in
Texas and Mexico
• It has been used medicinally and
sacramentally for thousands of years
• US government allows its use in Native
American religions
• Initial focus of Carlos Castenada’s “quest”
More peyote
• Users consume it in buttons
• Many initially experience nausea which is
followed by feelings of physical energy
(small doses) or visionary experiences
which they view as a spiritual and physical
blessing
• A recent study of regular Native American
users found no harmful cognitive or
psychological effects, and some gains!
Magic mushrooms
• Psilocybin, an active chemical compound
in hundreds of mushrooms that causes
hallucinogenic experiences
• Used world-wide especially by the Aztecs
• Can be smoked or simply eaten
• Castenada, and many others, sampled
• Most common natural hallucinogenic
lsd
• Officially lysergic acid diethylamide
• Accidentally discovered by a Swiss
chemist, Albert Hoffman, in 1943
• Somehow ingesting it, he experienced an
amazing shift in consciousness
• “An uninterrupted stream of fantastic
images of extraordinary vividness and
plasticity” passed before his eyes “
accompanied by an intense kaleidoscopic
play of colors”
Further “research”
• Hoffman went on to try LSD on many more
occasions
• These experiences were invariably
pleasant except once, when tired, he
mixed it with amphetamines and
experienced history’s first “bad trip”
• Recently turned 100, he still considers
LSD “medicine for the soul”
Then things got
weird
• The word slowly spread until in the early
60’s it reached Timothy Leary, a maverick
Harvard psychologist with extensive work
with psilocybin
• Leary experimented with his graduate
students and raved about LSD’s effects
reporting profound mystical and spiritual
experiences
• “Turn on. Tune in. Drop out.”
• “The most dangerous man in America.”?
The serotonin
connection
• LSD attaches to receptors usually used by
serotonin
• It apparently stimulates the receptors in
strange ways
• Change our typical perceptual filtering?
• Bad trips largely arise from the setting
• In secure environments, very unlikely
• Some suffer flashbacks, but still rare
ecstasy
• Also known as MDA or MDMA
• Synthetic compounds which resemble
neurotransmitters and stimulate serotonin
receptors
• Users report heightened intimacy and
insight into relationships
• Many negative effects – confusion, anxiety
• Evidence points towards damage to axons
devoted to serotonin
Crystal meth
• Also known as methamphetamine
• Causes extensive production of dopamine
• Ingestion leads to an almost instant tingly
rush of sexiness, confidence and alertness
• But eventually, dopamine receptors are
depleted and users feel unable to
experience pleasure without more and
more
A hurricane of
shattered bodies
and lives
• Addiction often follows with devastated
families, lost jobs, ruined health, crime, etc
• Horrible physical aftermath – premature
aging, skin sores, ruined teeth, wasting
• Burns victims overwhelm rural counties $$
• But for the Bush administration pot is still
enemy #1 – Local governments disagree