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 mid- 80’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

Other risks

• Evidence is building of a relationship between early pot use and the development of psychosis

• Use before the age of 15 can make vulnerable teens much more likely to eventually develop serious mental illness

• Genetic predispositions activated by environmental conditions

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 dream-like 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