Marijuana's been on people's
minds for a long time -- about as long as it's been in
people's minds. Consider:
More than 4,700 years ago, Chinese
emperor Shen-Nung listed it in the first guide to herbal medicine,
declaring it a useful treatment for everything from "female
weakness [to] absent-mindedness."
A thousand years ago, a legendary
Middle-Eastern cult that specialized in political murder was
paid in a form of the drug called hashish. Their name, hashishiyya,
still echoes in the English word "assassin."
In 19th Century France, a group
of artists and poets turned on to pot and tuned into their experiences
as a source of imagery and ideas. Their monthly gatherings formed
the basis of the book, The Club of the Hashishins.
But if marijuana made a splash
in centuries past, it was nothing like the tidal wave of interest
it's kicked up lately.
Today, marijuana is the most
widely-used illicit drug in the United States -- and in much
of the rest of the world. In fact, according to a recent survey,
more than 106 million Americans have tried pot, and about 16.7
million are regular users.
That's why we've put together
this pamphlet. Because marijuana's been poked and prodded, scrutinized
and analyzed more than any other drug in history.
What that's meant is a much more
complete -- and realistic -- picture of the full range of pot's
effects than we've ever had before.
We hope you'll stick around to
consider some of the more important ones.
Because marijuana is a complex
drug, and it can cause a lot of subtle (and not-so-subtle) changes
in the way we think and feel. And those changes are certainly
worth thinking about if you're thinking about marijuana.
..How does pot affect personality?
In a lot of ways. But fully understanding
all the ways it affects personality is like getting toothpaste
back into the tube: tricky, at best.
One reason pot is hard to pin
down is that it causes so many changes. In fact, researchers
now think of the marijuana high as a group of overlapping effects
involving different reactions in different body systems.
Still, what all the systems react
to is a chemical called tetrahydrocannabinol, or THC,
which triggers most of the mood and mind changes associated with
Much of our understanding of
how marijuana works is still sketchy, but it took a huge leap
forward with the 1992 discovery of receptors for THC in the brain,
docking sites for body chemicals much like THC.
Still, THC isn't the only chemical
that swings into action when pot does its stuff. That's because
marijuana isn't a single molecule at all (like alcohol or cocaine),
but at least 400 different compounds -- many of which, known
as cannabinoids, exist nowhere else in nature.
What THC and the other cannabinoids
do is temporarily tilt the balance of chemicals in the brain
involved in thought, feeling, and memory. Most effects -- from
changes in perception to feelings of relaxation and euphoria
-- usually peak within an hour and disappear altogether in 3-4
hours. Other effects may last longer.
..What other effects are there?
All kinds of effects.
But the most important revolve around several key systems:
- Coordination. Even low doses can slow responses, making
some tasks difficult, and others-driving, for example-potentially
- Perception. Pot subtly alters sensory perception. Effects can
include feelings of heightened sensitivity and a distorted sense
of the passage of time.
- Mental Changes.
Marijuana can impair
judgment and reasoning skills, particularly those involved in
counting and the ability to follow complex instructions. It also
temporarily disrupts short-term memory.
..Does that mean pot smokers develop amnesia
Not in the sense of forgetting
their own name -- although they might have a problem with yours,
if you were just introduced.
That's because THC loves to tinker
with short-term memory. Even occasional use can cause problems,
although it's more noticeable in heavy users.
Memory impairment shows up often
in tasks requiring sustained concentration, but it turns up elsewhere,
too. Communication is affected: speech slows, phrases get shorter,
and users can forget what they're talking about--even in the
middle of a sentence.
And even though performance and
memory problems usually disappear as drug effects fade, long-term
learning problems still haven't been ruled out.
..Are there other long-term risks?
Maybe. Because not all of pot's
effects necessarily disappear when the high subsides. Subtle
changes may continue.
In fact, one recent study showed
that pilots' flying skills were still impaired 24 hours after
smoking, even though the pilots themselves felt they were completely
back to normal.
And since THC breakdown products,
or metabolites, can linger in the body for days or weeks after
use, this could be risky -- particularly for those involved in
hazardous activities or occupations.
..Is pot stronger now than it used to be?
Yes and no. And maybe, definitely.
Government officials (especially
those who get the biggest headlines -- and budgetary bumps --
from escalations in the "War on Drugs") claim that
pot potency is up as much as ten times above levels of the 1970's.
Critics say such claims are based
on hype, not history. They cite figures from the federal government's
own analysis of 20,000 samples of confiscated pot tested over
the past 20 years.
Test results show little evidence
of surging marijuana potency -- except in the popular imagination
and the media. In fact, tests reveal average pot potency in the
United States to be fairly flat over the entire 20-year period,
averaging 2.9 percent THC.
Still, even if people occasionally
bend the truth, that doesn't mean the world isn't curved.
There is plenty of high-potency
pot out there -- and it causes plenty of problems for some users.
..Does pot cause psychological problems?
That's another question that's
hard to answer conclusively -- or quickly. But most authorities
agree that pot can contribute to problems in susceptible people.
The most serious risk that most
users ever face is anxiety, which can be triggered by stress
or fatigue and by higher-potency strains of marijuana. Such reactions
also tend to be more common among infrequent and inexperienced
Pot-related panic typically lasts
about an hour, and generally requires little more than time to
run its course, along with a little reassurance and TLC (not
to be confused with THC) from friends or helpers.
Longer-term problems are more
complicated and less-easily shrugged off. Particularly troubling
is a 2011 study, suggesting a link between cannabis use and the
onset of schizophrenia.
In analyzing data from 83 separate
studies involving more than 22,000 participants from around the
world, researchers found that cannabis smokers who develop psychotic
disorders typically do so 2.7 years earlier than non-smokers.
Cause and effect? Not for most
people, since few pot smokers become psychotic. Still, the study's
conclusion -- that pot use plays a "causal role" in
the onset of psychotic symptoms in at least some patients --
is worth thinking about and worth additional study.
Throughout history, no other
drug has attracted more heat or inspired more heated rhetoric
than marijuana. That's as true today as it's ever been.
And while we still haven't mastered
all the mysteries of marijuana, we're closer to understanding
it than we've been before.
We know it's a complex drug that
triggers complicated changes in the body and brain.
We also know it can cause a range
of reactions -- both pleasure and panic and possible longer-lasting
changes, depending on dose and frequency of use.
And we know that pot poses potentially-serious
risks to children, pregnant women, and those with underlying
And while we still don't know
all we'd like about the effects of occasional use, we do know
that people who smoke a lot of pot can have a lot of problems.
Don't be one of them.
Because problems -- whether they're
caused by pot or not -- can be a lot easier to prevent than they
are to predict.
..Sidebar 1 | Pot & Performance
Of all the charges leveled against
marijuana over the years, one that's stuck longest--and has been
most difficult to prove scientifically -- is its supposed link
to "amotivational syndrome."
Symptoms of amotivation -- which
include confusion, declining performance, and difficulty in finishing
tasks -- are common enough among heavy smokers.
For now, though, marijuana and
amotivation remains a chicken-and-egg question. Still unknown
(and perhaps unknowable) is whether pot causes amotivation, or
whether disaffected people smoke pot as a symptom of their alienation.
Similarly, changes that are sometimes
blamed on pot use by young people--including changes in appearance
and an increased desire for privacy -- are often only "symptoms"
of growing up.
..Sidebar 2 | Smoke Signals
In most ways, marijuana ranks
pretty low on the drug-problem totem pole. One reason: Pot's
low toxicity. People don't overdose or lose their lives from
smoking pot -- or at least not so anyone notices all at once.
Still, that doesn't mean people
don't have problems with marijuana. They do.
But unlike other drug problems,
signs of pot-related trouble may take a while to show up. And
even when they do appear, pot problems can look more like good
things that didn't happen in our lives than bad things that did.
How do you keep problems from
happening to you? Here are a couple of ways:
- Don't smoke
That's the easiest way to
avoid the issue. There's never been a documented case of anything
disastrous happening to someone suffering from acute (or
chronic) marijuana deficiency.
- If you smoke
a lot, cut down. People who smoke a lot are more likely
to suffer serious problems than occasional smokers.
And if not smoking for a day
or two makes you feel tense, tired, anxious, or depressed, you
might want to reconsider how much of your life you're devoting
to the garden of grass inside your mind. Chances are you'll want
to cultivate some new habits. Or weed out some old ones.