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This lecture is about drugs.
Meaning of course, illegal drugs.
Or to put it more correctly, drugs that
are illegal under most circumstances, in
most jurisdictions.
We can divide these illegal drugs into
three different types.
There are natural chemicals, mostly from
plants but also from other creatures.
And typically these have been used since
ancient times, mostly by people who you
might refer to as medicine men, and they
might have been used as medicines.
Morphine, for instance, from the opium
poppy, has been in
use for millennia, or they might be used
for religious experiences.
The so-called medicine men, or shamans,
might take the plants
that contain these substances and go into
some kind of hallucination
and think they're communing with the
spirits or the gods.
With the advent of modern chemistry in
the 19th century,
it became possible to take these
substances from nature and then modify
them by chemical, by artificial means,
to generate new compounds with different
activities.
And these modified natural compounds we
will refer to as semi-synthetic compounds.
An example of a semi-synthetic compound,
which in
this case is perfectly legal, would be
aspirin.
It's derived from a chemical that occurs
naturally in willow trees.
The last class are the purely synthetic
compounds.
And typically, these compounds have been
prepared
in the pharmaceutical industry for disease
treatment of
one kind or another, and somehow they have
started to be the subject of misuse.
In this category we might also include
abuse of solvents, paint sniffing and glue
sniffing.
But whichever category the compounds, the
chemicals, come
from, they can lead to physical and
psychological addiction.
It's certainly nothing new.
This is a quotation from Georg Steller,
who was
an early explorer in Siberia back in the
18th century.
And as he was travelling through the
wilderness of
Siberia, he came across this tribe who
really liked mushrooms.
But they didn't like mushrooms in the way
that you or I might
like mushrooms, maybe fried with a little
red wine and garlic or something.
They liked these mushrooms called the fly
agarics, which they would dry and eat.
And because of this chemical, ibotenic
acid, that is present in
the mushrooms, the people who ate them
would become intoxicated and hallucinate.
Now of course, these mushrooms were very
popular in this tribe, so they
commanded a high price so the poor people
couldn't afford the mushrooms themselves.
But according to Steller, what the poor
people would
do would be to collect the urine of the
people who had eaten the mushrooms and
then drink
the urine and get the same experience, if
not better.
And they could do this because the body
gets rid
of this ibotenic acid by excreting it
into the urine.
It's not just mushrooms.
This is the peyote cactus.
It contains the chemical mescaline, which
is biologically active.
And this cactus has been used in various
religions in Mexico for many, many years
and it spread to the Native Americans of
the south-west United States in the 19th
century,
and they too, used it for religious
purposes.
Because of the mescaline present in the
cactus, this is illegal in the United
States, with the exception of those who use
it for religious purposes.
One of the best known drugs that have come
to us from ancient times is cannabis,
which as you can see, is known by many
different names.
So in ancient times, cannabis was well
known throughout Asia, China and the
Middle East
and one of the uses for this plant was
very simply to make rope.
Hemp fibres turn out to make very good
rope
and nowadays in many countries, they're
used for
things like bags and sacks and so forth.
But certain parts of the plant contain
potent chemicals that act on the brain.
The first Europeans to come across
cannabis were possibly the Crusaders.
In the time of the Crusades, there was a
mysterious
organization run by the so-called Old Man
of the Mountains,
and this was an organization which would
supply assassins.
And the people who worked for this
organization, according to stories that are
passed
down, would do absolutely anything on the
orders of this Old Man of the Mountains.
One theory is that they would do this
because he kept them well fed on cannabis,
which is also known as hashish.
That is why we get this English word,
assassin.
It's derived from the Arabic hashish.
Certainly one of the first Europeans to
describe cannabis use was
Marco Polo, who travelled through these
regions on his trip to China.
And the cannabis habit was probably first
brought back to Europe by soldiers in
Napoleon's army after his ill-fated
invasion of Egypt and Syria.
In cannabis use, the typical method of
ingesting it is to take the herbal
material from the plant, which is cannabis
sativa, and then this is usually smoked.
The herbal material can be identified by
using the techniques of botany.
Investigators can look at the shape of the
leaves,
they can identify it by a characteristic
smell,
and a very characteristic point about
cannabis
leaves is the presence of small silica
particles
in the leaf which can be observed
under the microscope, which are called
cystolithic trichomes.
Cannabis sativa is the only member of its
family.
It doesn't have any close relatives with
which it can be confused.
In fact, the closest relative of the
cannabis plant is
the hop plant, which is used as a
flavouring for beer.
In addition to the herbal material,
cannabis may
also be consumed as cannabis resin and
cannabis oil.
Well, after processing, cannabis can turn
up in all sorts of products.
Here's an example, this is cannabis
flavoured
chocolate, and you can see the give-away
there,
the leaves.
And here's another example,
this is cannabis flavoured vodka.
Well, the biological activity of cannabis
is due largely to the presence of this
chemical here, delta eight
tetrahydrocannabinol, and this
has multiple effects upon the Central
Nervous System.
One thing that has been reported about
taking
cannabis is that the tetrahydrocannabinol
appears to be effective
against the very unpleasant side effects
that can
occur when people are taking anti-cancer
drugs,
that is, when people are undergoing
chemotherapy.
The side effects of chemotherapy can be
very, very unpleasant, and
some people have given up their
chemotherapy because of those side
effects.
So some people on chemotherapy have taken
to
smoking cannabis to get rid of those side
effects,
though nowadays, synthetic alternatives
are available,
which do not have the other effects of
cannabis.
And in some countries and some areas, it
is now legal to consume cannabis.
An example would be the U.S. state of
Colorado, which has just legalized it.
Well how can cannabis be obtained?
Well, either smuggled in from the country
of origin,
or it can be grown under the right
conditions.
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