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It's the world's favourite
illegal drug.

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I'm high on pot.

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Ganj, Buddha.

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Sticky Icky.

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Hemp, marijuana...

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In the UK alone,

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half of all 16 to 29-year-olds
have tried it least once.

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Now, for the first time ever,
follow an entire trip from start
to finish inside your body.

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A unique journey that will track
cannabis as it hijacks
the inner workings of our brain.

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It kind of goes pffff!

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See how it creates its heart-racing
and mind-warping effects.

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I don't know if I should have
eaten that whole cookie.

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Police!

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Alongside this drug trip,
we'll confront head-on

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the biggest myths and controversies
that surround this humble weed,

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by gaining exclusive access to
cutting-edge scientific research...

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I'd like you to breathe in...

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..to discover, is Cannabis addictive?

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Does it destroy our memory?

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Who's the Prime Minister?

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Er, Gordon Brown.

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Oh, no, God! No, David Cameron.

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And can it even lead to psychosis?

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Have you been receiving
any special messages?

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I feel like I've got some sort of
communication going on,

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like a conversation
with my boyfriend.

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Do you want to stop?
Are you all right?

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Discover once and for all
if this is a harmless herbal high,
or the ultimate bad trip.

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In the last month, around a million
and a half people in the UK have
rolled a spliff, smoked a pipe,

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sparked up a bong,
or eaten a space cake.

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They've used Thai stick or resin,

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skunk or chronic.

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Despite the fact that possession
of any type of cannabis

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now carries a maximum penalty
of five years in prison.

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26-year-old Imogen has just
returned home from her new job

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in the admin department of a large
consultancy firm in the City.

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OK. Today I'm moving house,
so I couldn't be more stressed.

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I am fairly broke,

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I don't drive,
I don't have a boyfriend,

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my family live in Cornwall,
so I've got no help,

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I've got no-one to be there for my
big stresses and give me a cuddle.

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It's all been really, really
last minute.

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I'm panicking and stressing and
wandering the house, going, "Huh?"

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So I'm just going to sit down
and say, "Sod it" for 20 minutes

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and have a smoke.

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After a long day at the office,
Imogen likes to unwind in
the evenings with a spliff or two.

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My little box of wonder.

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I don't really feel like I'm hurting
anyone or doing anything awful.

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I made the decision that it was
something that I enjoy

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and something that doesn't impact
on my life and I can make a genuine
risk assessment of that.

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There's always this moment when
you've had a stressful day,
you've come home and rolled

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your first spliff and you're
really looking forward to it
and you can't find your lighter!

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Ah, thank God.

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Mike is a straight A student
waiting for his A-level results.

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He's hoping to study history
at university.

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Mum found my pipe and I think she
was a bit worried about what it was.

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She assumed it was a crack pipe
or something.

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I was like, don't worry,
it's nothing sinister.

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I smoke it because
I like to smoke it.

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It's not because I need to,
it's like, why not?

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It makes things more fun,
it makes things better.

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Unlike Imogen, who smokes every day,

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Mike and his friends only like
to get high a couple of times
a week as a bit of fun.

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The two years I've been
smoking weed have coincided
with my best academic years.

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I'm not saying it caused it,
but it's obviously not had
a bad effect on me.

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Mike and Imogen and around
three million other people
in the UK get high regularly.

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That's a bit nice.

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It's not very well rolled.

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But why is this drug so appealing
to so many different people?

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And how does it actually work?

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This is where the journey begins.

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The cannabis smoke is inhaled.

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Our lungs are where we absorb oxygen
from the air, but they also absorb

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other chemicals, like those in smoke
from the joint when inhaled.

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Many smokers, like Mike
and his friends, believe that

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holding the smoke in their lungs
for up to 15 seconds
gives them a stronger high.

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They're wrong. It has no effect
on the intensity of the high.

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But it does jack up the amount
of tar they inhale,
to four times that of a cigarette.

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The tar attacks the small, hair-like
cilia that protect the lungs
and paralyses them.

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This allows the tar to penetrate,
leading to a greater risk
of chronic bronchitis.

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Once inhaled, the cannabis chemicals
slip easily

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through the membranes lining
the lungs and into the bloodstream.

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The blood carries them from the lungs
to the heart.

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Almost immediately, the blood vessels
relax and dilate,

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allowing the blood
to rush around the body.

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The body starts to feel warm
as excess blood flows to the skin.

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It surges to the tiny blood vessels
in the eyes, which turn red.

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Cool.

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What was it I said
to that guy in KFC yesterday?

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You said you'd like
the five piss chicken!

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I'm really warm.
Is anyone else really warm?
It's nice and warm, yeah.

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As the blood spreads around the body,
blood pressure starts to drop.

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If it drops far enough,
it can trigger a fainting reflex,
also known as a "whitey".

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A whitey is when you've had
too much of it

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and you throw up and it sends
your head really, like... whizzy.

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So Imogen's reaction is typical.

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I'm going to have to sit down.

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There's always that sort of...

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..first few drags where you go,
"And relax!"

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Within seconds of entering Imogen's
bloodstream, the most powerful
ingredient of cannabis,

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Delta-9 Tetrahydrocannabinol,
or THC, travels in the blood,

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up the spine and into the brain.

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You kick over from "I'm getting
high, I'm getting high"
to "I am high!"

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And it feels like your eyes
are opening up at the back

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and it's like a relief thing,
it kind of goes pfffff!

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Which is... fantastic!

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This high can last for up to two
hours and starts almost immediately.

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I feel kind of floaty,

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as opposed to
weighed down by stress.

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And, erm...

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I feel calm and just happy.

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One of the first effects is a buzz.

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For Mike, everything around him
suddenly seems a lot more vivid.

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When, like, the sun comes through
there, the trees, this sounds stupid
now, but it looks really nice.

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Is that all you wanted to say?
That's all I wanted to say.

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The sun looks really nice
through the trees?

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It's a few BLEEP trees, man!

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All right, sorry!

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Both Mike and Imogen think
they're just chilling,

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but they may be putting
themselves in danger.

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In the hour after smoking cannabis,
your risk of having a heart attack
increases fivefold.

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The THC in their blood has lowered
their blood pressure.

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The heart senses this
and starts to beat faster and faster,

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increasing its speed
by up to 50 per cent.

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Which makes this a bad idea,
especially for anyone with
a history of heart trouble.

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That's a bit sad, it's almost over.

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Cannabis affects the way we think,
feel and move in ways unmatched
by any other drug.

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The cannabis plant has actually
been around far longer than humans,
over 30 million years longer.

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Its first recorded use by people was
in China, almost 5,000 years ago.

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By the 1960s, this mysterious weed
was pretty much everywhere.

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But scientists were stumped on
the nuts and bolts of how it worked.

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So they set out to monitor its
effects on very willing subjects.

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None of us know very much about
this drug in any verifiable way.

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So, Bill, it's been about
two hours since you got the drug.

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How do you feel?

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Fantastic!

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We found out that the drug
makes people happy,

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it makes them intoxicated
and finally, it makes them sleepy.

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Dr William Notcutt has spent the last
17 years studying how cannabis works.

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What I think is quite amazing,

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that here is a plant that grows
wild across half the world

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that produces a chemical
that somehow gets into the brain,

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which is quite well protected in
the body against strange chemicals.

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Yet, it gets into the brain
to produce an effect within
the brain and within the body.

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It was only in 1988 that scientists
made a dramatic discovery -

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our bodies are hardwired
to react to cannabis.

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Our brain tells our body what to do
by using our nervous system.

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This living communication network
stretches from our brain

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down to our spine
and out through our body.

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It allows us to see, hear and feel
the world around us and react to it.

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When you smoke a joint, cannabis
penetrates deep into the brain

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and hijacks the nervous system
like a herbal terrorist.

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The human brain is composed
of networks of billions
of long nerve cells.

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Messages pass from one cell
to the next across narrow gaps.

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On either side of the gap
are tiny gates that control
this flow of information.

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They're called receptors.

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The THC molecule penetrates the brain
and seizes control of the receptor.

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Once it controls the receptors,
it controls how they work.

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These receptors show up
in especially high numbers

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in the areas of the brain that
regulate our memory, appetite,
thoughts and mood.

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So it's here that cannabis
works its magic.

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It makes you high, this is the
expression that's usually used.

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It makes them feel very good,

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forget their cares and worries and
sends them up on top of the clouds.

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Cannabis is a big part of 20-year-old
Chet and 18-year-old Alex's lives.

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I found when I first tried it,
all my senses were enhanced,

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so taste, touch, smell,
everything seemed a lot clearer.

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It puts you in this bubble
for a few hours where you don't
worry about anything.

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They like to get high
several times a day.

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Best experience of getting high?
Oh, God!

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Just the culture around it,
making friends and meeting people.

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I met Alex cos we realized
we were both stoned in class.

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We both just said,
"Man, I'm so high!"

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And from that day, we just clicked.

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And we've been really good friends
ever since.

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Unlike Alex, Chet still isn't sure
if he wants to go university.

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Alex is more motivated then me.
Yeah, I'm going to uni
and everything.

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Tonight, they're making
weed flapjacks.

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Five what? Ounces.

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Unlike other drugs like cocaine
or speed, cannabis doesn't break down
in water, only in oil.

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Or in this case, butter.

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So if we heat the weed ground up
in the butter, then all the stuff

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that gets you high in the weed
will go into the butter.

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THC!
And then you get stoned, eventually.

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If they're caught, they'll face
the same penalty as they would for
possession of any form of cannabis.

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About six months ago,
Chet's passion for weed
turned into more of an obsession.

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Check the pot in the pot.

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It got a bit much. I was homeless,
squatting in this little house,

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with no heat, just getting stoned
all the time.

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And it looked like a crack den,
it was pretty horrible.

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And that was really all I was doing
with my time,

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just getting people over and getting
stoned. And it stopped being fun.

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Smells great.
It smells really weedy.

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Chet now tries to limit the amount
he gets high.

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Smoking cannabis is supposed to be
away from routine and everyday life.

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It's supposed to get you
away from that.

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And if it becomes that,
that's when it becomes a problem.

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So you've got to keep it fun,
really.

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Mate! These are looking well good.

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The weed flapjacks are ready, and the
guys are hoping they'll make a walk
in the forest a lot more interesting.

201
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Oh, wow, that looks cool.

202
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I like the forest. Let's eat them,
then walk, it takes a little while.

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So, what happens to the body
when cannabis is eaten,
rather than smoked?

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You can see green in them.

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I like the taste of weed anyway.
It's quite nice. It's herby.

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The cannabis is swallowed
in the lumps of flapjack
and travels to the stomach,

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where it starts being broken down
by the digestive juices.

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But digestion is a relatively slow
process compared to the instant high
of smoking a joint.

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It's also riskier.

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When you're smoking, it's pretty
much instant when you feel
the effects,

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so you can stop if it's too much,
or you can carry on if you want.

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But with edibles, it takes
a couple of hours to come up.

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And then, like, if you eat a couple,

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you don't know how hard it's going
to hit you once it comes in.

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Contrary to popular opinion, eating
weed doesn't make it any stronger.

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Only about a tenth of the
mind-altering THC is absorbed,

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versus up to five times that
when it's smoked.

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But once the high hits, it lasts
a lot longer, around six hours.

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I don't know if I should have
eaten that whole cookie!

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After about 45 minutes, their weed
flapjacks are almost fully digested.

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The THC slips through the walls
of their small intestine
and enters the bloodstream.

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It travels in their blood, up their
bodies, to the back of the neck,

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where it enters into a part of
the brain called the hypothalamus.

224
00:18:23,440 --> 00:18:25,560
This is the control centre
for hunger.

225
00:18:27,400 --> 00:18:31,040
THC locks onto the receptors here
and starts flooding their bodies

226
00:18:31,040 --> 00:18:34,560
with messages telling them
to seek out food,

227
00:18:34,560 --> 00:18:36,560
whether they're hungry or not.

228
00:18:38,160 --> 00:18:43,120
Most people just call this
the "munchies", and they're
almost impossible to resist.

229
00:18:43,120 --> 00:18:45,000
I really want to eat a muffin
so bad!

230
00:18:47,200 --> 00:18:48,840
Yay!

231
00:18:52,520 --> 00:18:59,680
Another risk is if they gorge
on more cannabis cakes,
they could get higher and higher.

232
00:18:59,680 --> 00:19:03,800
Luckily, these muffins don't have
any weed in them.

233
00:19:07,560 --> 00:19:11,280
HE MAKES BEATBOX NOISES

234
00:19:11,280 --> 00:19:16,400
It's 15 minutes later,
and the forest has never looked
more beautiful to them.

235
00:19:16,400 --> 00:19:18,240
Yeah, they're all sparkling.

236
00:19:21,680 --> 00:19:26,360
Drugs definitely, like, helped me
get an interest in nature,

237
00:19:26,360 --> 00:19:29,640
just from being high in the forest

238
00:19:29,640 --> 00:19:31,680
and looking at it,
and how cool it is.

239
00:19:31,680 --> 00:19:35,080
It's the simple things that make you
smile when you're high.

240
00:19:35,080 --> 00:19:38,000
Like puddles!

241
00:19:38,000 --> 00:19:42,360
But what exactly is it that makes
even puddles seem so interesting?

242
00:19:42,360 --> 00:19:43,560
Inhale.

243
00:19:43,560 --> 00:19:47,960
Keep going, keep inhaling, come on.

244
00:19:47,960 --> 00:19:53,760
For years, scientists have been
trying to pin down how the world
looks to our brain when we're high.

245
00:19:53,760 --> 00:19:57,200
Left hand bend coming up,
going into third gear.

246
00:19:57,200 --> 00:20:03,720
This subject is driving quite
efficiently and carefully,
but he is in fact high.

247
00:20:03,720 --> 00:20:07,760
There's no slack in that at all.

248
00:20:11,360 --> 00:20:16,360
Now some ground-breaking new research
is going to help 23-year-old Ravi

249
00:20:16,360 --> 00:20:20,640
get a window into what happens
inside his brain when he gets stoned.

250
00:20:23,360 --> 00:20:27,160
A postgraduate student,
he only gets high at the weekends.

251
00:20:27,160 --> 00:20:31,720
I used to smoke a lot more at
university, generally with friends.

252
00:20:31,720 --> 00:20:34,680
It's just really nice
on a sunny day in a park.

253
00:20:34,680 --> 00:20:39,520
It's quite social, I suppose.
It's fun. It's just really pleasant,
you feel really relaxed.

254
00:20:39,520 --> 00:20:44,440
Today, at University College London,
he'll be part of a unique experiment.

255
00:20:44,440 --> 00:20:49,880
It should reveal if this pleasant
pastime damages his brain function.

256
00:20:49,880 --> 00:20:52,080
Ravi, I'd like you to breathe in.

257
00:20:53,600 --> 00:20:57,280
Ravi inhales pure THC through
a vaporiser, which heats the drug

258
00:20:57,280 --> 00:21:02,440
without allowing it to combust,
so it's less harmful to his lungs.

259
00:21:06,560 --> 00:21:12,520
Just as it does when smoked in
a joint, the THC travels through
his lungs and into his bloodstream.

260
00:21:12,520 --> 00:21:17,680
Within seconds, it hits his brain
and gets to work.

261
00:21:20,840 --> 00:21:24,560
How are you feeling?
Everybody happy. Yeah. Stoned?

262
00:21:24,560 --> 00:21:26,240
Yeah, feeling something.

263
00:21:26,240 --> 00:21:29,120
First up, a simple memory test.

264
00:21:29,120 --> 00:21:34,280
How old are you? 23.
What's the date? 30th of July.

265
00:21:34,280 --> 00:21:35,680
Who's the Prime Minister?

266
00:21:35,680 --> 00:21:38,960
Gordon Brown.
Oh, no, God! No, David Cameron.

267
00:21:40,720 --> 00:21:46,040
It's not a good start. Now, Ravi
must take a more testing memory test.

268
00:21:47,960 --> 00:21:51,560
He's played a 20-second news story.

269
00:21:51,560 --> 00:21:54,480
'Local police are collaborating
with CID...'

270
00:21:54,480 --> 00:21:58,760
Deep inside Ravi's brain
is the hippocampus.

271
00:21:58,760 --> 00:22:01,800
This is his memory centre.

272
00:22:01,800 --> 00:22:05,680
Surprisingly, one of its main
functions isn't to remember,

273
00:22:05,680 --> 00:22:08,120
but to forget.

274
00:22:12,520 --> 00:22:15,400
We can't remember everything
we see and hear.

275
00:22:17,280 --> 00:22:21,760
Every face, every car,
every story we're told.

276
00:22:21,760 --> 00:22:23,640
It would clog up our brains.

277
00:22:26,760 --> 00:22:32,800
So this is where the brain decides
what's worth keeping as a memory,
and what should just be chucked away.

278
00:22:37,120 --> 00:22:43,240
It's also an area of the brain
that has a lot of receptors that are
vulnerable to a takeover by THC.

279
00:22:45,880 --> 00:22:51,960
Almost immediately, the THC
turns up the dial on messages
telling Ravi's brain to forget.

280
00:22:51,960 --> 00:22:57,680
So, all new information risks
being rejected before it gets
a chance to become a memory.

281
00:22:57,680 --> 00:23:01,360
'..large houses in Cheshire
last month.'

282
00:23:01,360 --> 00:23:05,160
Now, Ravi must try and repeat back
the story.

283
00:23:05,160 --> 00:23:09,520
Um, thieves were caught on
the manor of Lord Dartston.

284
00:23:09,520 --> 00:23:15,160
Um, yesterday. And a, er...

285
00:23:15,160 --> 00:23:19,160
police investigation
has been launched.

286
00:23:21,760 --> 00:23:23,800
That's pretty much
all I can remember.

287
00:23:28,680 --> 00:23:33,840
The good news is, Ravi probably won't
recall how badly he did on this test.

288
00:23:33,840 --> 00:23:37,200
We know when people are intoxicated,
their memory is impaired,

289
00:23:37,200 --> 00:23:41,120
but chronically, so longer term,
the results have been equivocal.

290
00:23:41,120 --> 00:23:47,000
There seems to be little
longer term memory impairment in
the majority of cannabis users.

291
00:23:47,000 --> 00:23:53,560
But Ravi's damaged short-term memory
could be having an unexpected
benefit. G.

292
00:23:53,560 --> 00:23:58,520
He's asked to come up with
as many words starting with
the same letter as he can.

293
00:23:58,520 --> 00:24:01,440
Gregarious, gracious,

294
00:24:01,440 --> 00:24:06,040
grange, grog, gnome.

295
00:24:06,040 --> 00:24:09,120
And on this test,
he seems to be doing very well.

296
00:24:09,120 --> 00:24:10,800
Grip.

297
00:24:10,800 --> 00:24:13,400
Um, gustation.

298
00:24:13,400 --> 00:24:17,080
What we found so far is that verbal
fluency goes up, so people can

299
00:24:17,080 --> 00:24:20,760
generate more words when they're
stoned compared to when they're not.

300
00:24:20,760 --> 00:24:23,000
And we think cannabis
might make it easier

301
00:24:23,000 --> 00:24:27,120
for you to make associations between
concepts and words in your brain.

302
00:24:27,120 --> 00:24:31,800
Some people say it helps them
with problem-solving or creativity.

303
00:24:33,840 --> 00:24:39,360
It could be that, by halting the flow
of new information into our brain,
we are less distracted.

304
00:24:39,360 --> 00:24:43,640
So we start making new connections
in our mind.

305
00:24:43,640 --> 00:24:46,520
As a tree, I was...
I could be a tree...

306
00:24:46,520 --> 00:24:50,600
This could explain why everyone
from jazz musicians

307
00:24:50,600 --> 00:24:54,520
to computer programmers
have looked to weed for inspiration.

308
00:24:54,520 --> 00:24:58,120
When I'm high, it enhances
my creativity.

309
00:24:58,120 --> 00:25:03,160
One was painted before
going up on weed,
and the other while high on weed.

310
00:25:05,880 --> 00:25:08,760
HE BEATBOXES

311
00:25:10,240 --> 00:25:13,000
Wow! Look how cool that looks.

312
00:25:13,000 --> 00:25:17,800
It looks awesome.
It looks like Jurassic Park!

313
00:25:19,840 --> 00:25:25,840
It's been an hour and a half since
Chet and Alex ate their flapjacks.

314
00:25:25,840 --> 00:25:29,440
Their impaired memory is about
to affect their ability to navigate.

315
00:25:33,480 --> 00:25:35,960
We're going downhill. Yep.

316
00:25:35,960 --> 00:25:38,400
We're definitely going downhill.

317
00:25:38,400 --> 00:25:42,960
How are we getting in there?
Um, jump!

318
00:25:42,960 --> 00:25:45,960
Rocket boots.
Go across, we can jump there.

319
00:25:45,960 --> 00:25:47,600
We can't jump that!

320
00:25:47,600 --> 00:25:49,880
Does it look jumpable? Yeah.

321
00:25:49,880 --> 00:25:52,720
Actually, I'm not too sure of this.

322
00:25:57,280 --> 00:26:01,920
The hippocampus is where
the brain stores information
about every move we've ever made.

323
00:26:03,440 --> 00:26:07,880
We call on this database to work out
how to achieve all physical tasks,

324
00:26:07,880 --> 00:26:10,920
like jumping a ditch.

325
00:26:10,920 --> 00:26:16,200
But the THC in the cannabis
is interfering with the messages
to and from the database,

326
00:26:16,200 --> 00:26:21,440
so the brain's no longer sure
what the body can and can't do.

327
00:26:21,440 --> 00:26:26,120
What the f... Especially when it's
confronted with yet another ditch.

328
00:26:26,120 --> 00:26:28,480
That's not jumpable, actually.

329
00:26:28,480 --> 00:26:31,520
That is jumpable. Perseverance.

330
00:26:31,520 --> 00:26:37,720
The abyss they see before them is
actually a shallow ditch that's three
feet wide and a couple of feet deep.

331
00:26:37,720 --> 00:26:41,320
That looks like it gets deep really
early. It looks pretty dangerous.

332
00:26:41,320 --> 00:26:44,640
Yeah, another obstacle
for the stoner video game.

333
00:26:46,160 --> 00:26:48,320
He's shaking, he's shaking!

334
00:26:48,320 --> 00:26:50,120
We've all got to get across here.

335
00:26:51,760 --> 00:26:56,800
The THC also hijacks messages to
the part of their brain that controls
balance and coordination.

336
00:26:56,800 --> 00:26:59,960
Just jump, Alex, jump.

337
00:26:59,960 --> 00:27:05,680
So, even whey they picture a smooth
leap in their mind, the message can't
get through to their body.

338
00:27:05,680 --> 00:27:08,000
Put one up and then spring off.

339
00:27:09,520 --> 00:27:12,800
Eventually, the lads cross the ditch,

340
00:27:12,800 --> 00:27:17,880
in one piece. Sick! We did it.

341
00:27:17,880 --> 00:27:22,840
When cannabis distorts the messaging
system between our brain

342
00:27:22,840 --> 00:27:27,920
and our limbs, it can turn a
straightforward walk in the forest
into a complex obstacle course.

343
00:27:30,320 --> 00:27:36,880
It's been a bit of struggle,
but Imogen has moved most of
her stuff out of her bedroom.

344
00:27:36,880 --> 00:27:41,280
But the effects of the joint
that she smoked an hour ago
are starting to wear off.

345
00:27:41,280 --> 00:27:44,480
And her thoughts soon turn
to having another one.

346
00:27:44,480 --> 00:27:47,640
I'm going to grab a drink
and a smoke of J.

347
00:27:47,640 --> 00:27:51,560
Now, I definitely feel like
this is a reward. Happy days.

348
00:27:51,560 --> 00:27:58,000
Most users like Imogen think of
cannabis as being a relatively safe,
natural drug.

349
00:27:58,000 --> 00:28:03,800
But the more cannabis she smokes,
the more she needs to smoke to feel
its pleasurable effects.

350
00:28:03,800 --> 00:28:07,880
So, the big question is,
is it addictive?

351
00:28:07,880 --> 00:28:11,120
The idea of waking up one morning
and saying,

352
00:28:11,120 --> 00:28:15,960
"From this day forth, I shall never
smoke marijuana again,"

353
00:28:15,960 --> 00:28:19,480
is as stupid as...

354
00:28:19,480 --> 00:28:24,000
giving up chocolate
or carbohydrates.

355
00:28:24,000 --> 00:28:25,800
It's like...

356
00:28:27,520 --> 00:28:32,960
..I could do that and maybe
I would be healthier or thinner.

357
00:28:35,160 --> 00:28:37,560
But I certainly wouldn't be happier.

358
00:28:37,560 --> 00:28:41,240
And...is it really that big a deal? 

359
00:28:48,200 --> 00:28:51,880
But most experts agree that users,
especially those who smoke heavily,

360
00:28:51,880 --> 00:28:53,640
can become dependent on cannabis.

361
00:28:56,200 --> 00:29:00,240
25-year-old Chris works full-time
in a popular restaurant chain.

362
00:29:01,120 --> 00:29:04,560
I smoke weed all the time, usually
I smoke a bong and I'll be smoking

363
00:29:04,560 --> 00:29:08,000
that from the moment
I wake up in the morning.

364
00:29:08,000 --> 00:29:12,400
And then I'll come home from work
and smoke a bit. I'm always stoned.

365
00:29:12,400 --> 00:29:16,040
It's not good,
but that's the way I am.

366
00:29:16,040 --> 00:29:19,480
Chris first got high
when he was just eleven.

367
00:29:19,480 --> 00:29:23,080
That's, like,
more than half my life.

368
00:29:23,080 --> 00:29:25,800
The thing that gets to me
about smoking cannabis is,

369
00:29:25,800 --> 00:29:27,720
what have I got to show for it,
really?

370
00:29:27,720 --> 00:29:32,160
I've got a job, I do work, but
most of my money goes on to weed.
Everything goes on to weed.

371
00:29:32,160 --> 00:29:35,760
This is the room that I tend
to smoke cannabis in.
I watch telly here.

372
00:29:35,760 --> 00:29:39,600
I lie down and chill out
and watch the world go by.

373
00:29:39,600 --> 00:29:42,840
It's just crap,
it's no way of living, basically.

374
00:29:42,840 --> 00:29:46,800
Until he quits, his girlfriend
won't let him move in with her.

375
00:29:46,800 --> 00:29:48,960
I'd love to be in a better job,
in college,

376
00:29:48,960 --> 00:29:52,520
spending more time in a happier
relationship with my girlfriend.

377
00:29:52,520 --> 00:29:55,840
It's really hard, actually.

378
00:29:55,840 --> 00:30:00,480
The question is,
when does habit turn into dependency?

379
00:30:00,480 --> 00:30:03,920
If you keep using it, when you
experience negative consequences,

380
00:30:03,920 --> 00:30:08,040
so you're dropping out of school,
your relationships
are going downhill.

381
00:30:08,040 --> 00:30:12,240
You get anxious
when you don't get the drug.
You get massive cravings for it.

382
00:30:14,040 --> 00:30:17,520
Chris's girlfriend Rachel
believes he has a problem.

383
00:30:17,520 --> 00:30:23,880
For you, it's not for the buzz,
it's just feeling like
it's chilling you out. Yeah.

384
00:30:23,880 --> 00:30:26,440
But, to me,
it's not chilling you out.

385
00:30:26,440 --> 00:30:28,760
I am dependent on cannabis.

386
00:30:28,760 --> 00:30:32,080
When she's taken me weed off me
in an argument and she's held it,

387
00:30:32,080 --> 00:30:36,200
and I've grabbed her hand, she's
like, "No, you're not having it."

388
00:30:36,200 --> 00:30:38,360
And I've really
thought she was taking it

389
00:30:38,360 --> 00:30:41,080
and throwing it away,
so I've really wanted it back.

390
00:30:41,080 --> 00:30:44,560
So I'm really like scuffling
with her to try and get it back.

391
00:30:44,560 --> 00:30:48,120
That was a bad time, because
I really stood back afterwards

392
00:30:48,120 --> 00:30:51,080
and thought, "You muppet,
look at how you've just been."

393
00:30:51,080 --> 00:30:56,400
Cannabis is now the second
most common drug of referral
to rehab clinics, after heroin.

394
00:30:56,400 --> 00:30:58,920
I love you. I love you.
Do you? Yeah.

395
00:30:58,920 --> 00:31:05,280
Chris has decided to quit,
but after 14 years of getting high,
it's not going to be easy.

396
00:31:05,280 --> 00:31:10,160
He heads back to his flat,
for his last smoke ever.

397
00:31:17,080 --> 00:31:21,520
An estimated one in ten smokers
will become dependent on cannabis.

398
00:31:25,680 --> 00:31:30,080
It's sad, really,
sitting here smoking weed on my own.

399
00:31:30,080 --> 00:31:35,560
Quitting cannabis doesn't lead
to dramatic cold turkey effects,
like harder drugs.

400
00:31:35,560 --> 00:31:38,440
The withdrawal symptoms
are quite hard to specify,

401
00:31:38,440 --> 00:31:43,720
but people generally experience
things like not being able to sleep
and increased anxiety.

402
00:31:45,240 --> 00:31:49,240
Other symptoms include irritability
and decreased appetite -

403
00:31:49,240 --> 00:31:53,200
the exact opposite
of the positive effects of cannabis.

404
00:31:53,200 --> 00:31:55,880
Smoking weed is bad.

405
00:31:55,880 --> 00:32:01,080
For Chris, quitting will be
particularly difficult, because he
is also addicted to cigarettes.

406
00:32:01,080 --> 00:32:02,400
This is last my last bong.

407
00:32:05,840 --> 00:32:09,200
His withdrawal symptoms should
begin within about one day,

408
00:32:09,200 --> 00:32:13,560
peak at two to three days
and subside within one to two weeks.

409
00:32:15,600 --> 00:32:17,640
No more weed now.

410
00:32:17,640 --> 00:32:20,720
His girlfriend will record
his experience on a camcorder.

411
00:32:20,720 --> 00:32:23,560
What time is it? 12.51am.

412
00:32:29,600 --> 00:32:33,080
By the next morning, Chris is
already starting to struggle.

413
00:32:38,560 --> 00:32:41,320
Don't take the piss out of me.
You're taking the piss?

414
00:32:44,280 --> 00:32:46,720
Don't take the mick. I'm not.

415
00:32:48,800 --> 00:32:51,280
I'm really being serious,
don't take the mick.

416
00:32:51,280 --> 00:32:54,440
What was you just saying,
what do you want to do?

417
00:32:54,440 --> 00:32:59,680
By evening,
he's back at his flat getting high.

418
00:32:59,680 --> 00:33:04,600
He was feeling it thought,
weren't you? Yeah, I did
try to stop smoking weed.

419
00:33:04,600 --> 00:33:09,160
Twice I stopped smoking weed,
but found it really hard.

420
00:33:09,160 --> 00:33:15,600
I did do my best. I didn't
smoke weed all the next day,
after I took my last mix.

421
00:33:15,600 --> 00:33:18,920
And then, come to night-time,
I was really feeling it.

422
00:33:18,920 --> 00:33:23,040
I was just stressing
and kicking off and I ended up
going and having a smoke.

423
00:33:23,040 --> 00:33:25,320
They just think people
can get off it easily -

424
00:33:25,320 --> 00:33:27,800
and I suppose you can,
but it's not that simple.

425
00:33:28,840 --> 00:33:30,520
Chris is not alone.

426
00:33:32,360 --> 00:33:36,160
The rates of addiction
to cannabis are rising steadily.

427
00:33:36,160 --> 00:33:43,200
Experts believe this
could be down to one thing -
the arrival of super-strong skunk.

428
00:33:47,560 --> 00:33:52,800
Police seizures show that skunk
accounted for barely 10% of the
cannabis sold here in the late 1990s.

429
00:33:52,800 --> 00:33:56,480
Last year, it was 80%.

430
00:33:58,200 --> 00:34:02,760
But can a plant really be to blame
for reactions like these?

431
00:34:02,760 --> 00:34:07,360
Your hear voices and they sometimes
control you to do something.

432
00:34:09,320 --> 00:34:12,680
The reason that I'm saying three
to these statements is because,

433
00:34:12,680 --> 00:34:14,640
they go into my head
and it happens.

434
00:34:14,640 --> 00:34:17,200
Are we sitting
on a mental health time bomb?

435
00:34:17,200 --> 00:34:19,840
..increased risk of
depression and schizophrenia...

436
00:34:19,840 --> 00:34:23,080
Skunk, why is it so strong
and potentially dangerous?

437
00:34:24,600 --> 00:34:28,280
Skunk is the name given to
genetically-engineered weed,

438
00:34:28,280 --> 00:34:32,960
designed to deliver the maximum
dose of mind-altering THC.

439
00:34:32,960 --> 00:34:38,360
I don't like the word "skunk",
because I think it's just a bit
like a fear-mongering sort of word.

440
00:34:40,200 --> 00:34:43,800
Grown under hot lights in enclosed
spaces, the female plants are kept

441
00:34:43,800 --> 00:34:46,160
in a perpetual state
of sexual frustration.

442
00:34:48,200 --> 00:34:52,360
They overproduce THC,
to attract pollen from male plants
that don't exist.

443
00:34:54,800 --> 00:34:59,000
The best skunk you get
will smell ever so slightly

444
00:34:59,000 --> 00:35:02,200
like an alleyway that cats
have been doing their business in.

445
00:35:02,200 --> 00:35:08,760
In this hothouse environment,
levels of THC can soar to five
times that of ordinary cannabis.

446
00:35:08,760 --> 00:35:12,560
The first time I remember smoking
it, ten seconds later, I just

447
00:35:12,560 --> 00:35:17,160
fell backwards on to the bed and
just lay there for about 15 minutes.

448
00:35:18,320 --> 00:35:23,600
But Chet and Alex,
and Imogen and Mike,
all continue to smoke skunk.

449
00:35:25,680 --> 00:35:29,600
So how strong is the evidence
that skunk leads to mental illness?

450
00:35:30,920 --> 00:35:35,360
In South London,
psychiatrist, Dr Robin Murray,
has been studying the subject

451
00:35:35,360 --> 00:35:38,480
for the last eight years -
and he's convinced there is a link.

452
00:35:40,680 --> 00:35:42,000
'The people that we see'

453
00:35:42,000 --> 00:35:46,080
have usually been smoking
cannabis for at least five years.

454
00:35:46,080 --> 00:35:51,360
They're smoking every day
and they are particularly
likely to be smoking skunk.

455
00:35:51,360 --> 00:35:57,200
In his patients, this combination
appears to lead to a condition
known as psychosis.

456
00:36:01,600 --> 00:36:05,920
Psychosis is the ultimate bad trip,
an altered mental state that can

457
00:36:05,920 --> 00:36:08,720
include hallucinations
and severe paranoia.

458
00:36:10,240 --> 00:36:14,680
So, anybody who has
a hallucination or a delusion,

459
00:36:14,680 --> 00:36:16,240
we would regard as psychotic.

460
00:36:16,240 --> 00:36:22,160
Sometimes these illnesses last
for a few days, or a week or two.

461
00:36:22,160 --> 00:36:26,440
But if they last for months or
years, we term them "schizophrenia".

462
00:36:29,480 --> 00:36:34,680
31-year-old David can still
remember his first joint clearly.

463
00:36:34,680 --> 00:36:36,640
'My friends called me over,
when I was'

464
00:36:36,640 --> 00:36:39,560
over the field and they said,

465
00:36:39,560 --> 00:36:41,600
"Come on, Dave,
we're having a smoke."

466
00:36:41,600 --> 00:36:44,840
And I said, "Yeah OK." I thought,
I've never tried this before.

467
00:36:44,840 --> 00:36:47,240
I had, about, a joint.

468
00:36:47,240 --> 00:36:49,240
After that,
I just couldn't stand up.

469
00:36:49,240 --> 00:36:52,880
I had a massive head rush,
I thought, "I'm not going
to do that again."

470
00:36:52,880 --> 00:36:57,920
But when you say to yourself
you're not going to do cannabis
again, you do it again.

471
00:36:57,920 --> 00:37:03,000
His father died when he was seven
and his mother Jo brought up
him and his sister.

472
00:37:03,000 --> 00:37:07,640
Yes, Dave, I'm fine. How are you?
Yeah, I'm all right. Did you get
the bus over? Yes, I did.

473
00:37:07,640 --> 00:37:12,320
He started getting high
when he was 13 and he was
soon smoking weed regularly.

474
00:37:12,320 --> 00:37:16,840
Before long, he started
having strange experiences.

475
00:37:16,840 --> 00:37:20,560
I was walking home
and I heard noises from the bus,

476
00:37:20,560 --> 00:37:24,680
like, the whole..
people on the bus were, like,

477
00:37:24,680 --> 00:37:28,880
spitting
and it sounded like raindrops.

478
00:37:28,880 --> 00:37:34,680
Jo had no idea her son
was getting high until, after just
three months of smoking,

479
00:37:34,680 --> 00:37:37,440
his paranoia
spiralled out of control.

480
00:37:37,440 --> 00:37:40,040
Do you remember this one?

481
00:37:40,040 --> 00:37:42,240
Yeah, I do.

482
00:37:42,240 --> 00:37:44,880
'David was bit agitated.'

483
00:37:44,880 --> 00:37:51,080
We were standing in the kitchen and
he had a small hammer in his hand

484
00:37:51,080 --> 00:37:54,880
and he said to me,
"You're NOT my mum."

485
00:37:56,800 --> 00:38:01,840
You hear voices and they sometimes
control you to do something,

486
00:38:01,840 --> 00:38:04,800
that you have no control over.

487
00:38:04,800 --> 00:38:07,080
Yeah, that was
when I was in hospital.

488
00:38:07,080 --> 00:38:13,400
David was diagnosed as a paranoid
schizophrenic and remained in a
psychiatric unit for ten years.

489
00:38:13,400 --> 00:38:16,800
This is the other one, David.
You look very thoughtful there.

490
00:38:16,800 --> 00:38:20,680
The big question is,
how much is cannabis to blame
for David's condition?

491
00:38:20,680 --> 00:38:22,920
That question is rather like saying,

492
00:38:22,920 --> 00:38:27,160
could smoking cigarettes,
on its own, cause a heart attack?

493
00:38:27,160 --> 00:38:32,960
Many disorders result
from a combination of risk factors.

494
00:38:32,960 --> 00:38:39,480
For schizophrenia,
having a family history,
some difficulties in childhood -

495
00:38:39,480 --> 00:38:45,400
a parent dying, for example -
these all add up. And cannabis
is one of these risk factors.

496
00:38:45,400 --> 00:38:53,000
It's only now that Jo can see how
her husband's early death affected
her son in more ways than one.

497
00:38:53,000 --> 00:38:57,160
I didn't know
that David's father

498
00:38:57,160 --> 00:39:01,440
had a mental illness
until David's father killed himself.

499
00:39:01,440 --> 00:39:02,960
I didn't mean to take it.

500
00:39:02,960 --> 00:39:06,560
When I think about it, I wish I'd
never tried it in the first place.

501
00:39:08,560 --> 00:39:14,040
But the precise nature of the link
between skunk and psychosis
still remains unclear.

502
00:39:18,360 --> 00:39:21,960
Chet and Alex and their friends ate
their weed flapjacks two hours ago

503
00:39:21,960 --> 00:39:24,920
and things have taken
a turn for the worse.

504
00:39:24,920 --> 00:39:27,280
Urgh.

505
00:39:28,040 --> 00:39:33,160
Following the initial euphoria,
users can start to feel
anxious or distrustful.

506
00:39:33,160 --> 00:39:36,240
I just heard someone shout.
Yeah, the same.

507
00:39:36,240 --> 00:39:39,120
So how does a normal high
turn into paranoia?

508
00:39:40,720 --> 00:39:44,320
Scientists suspect it could be
down to a chemical in our brain

509
00:39:44,320 --> 00:39:47,240
that makes us focus our attention
on our surroundings.

510
00:39:47,240 --> 00:39:50,440
I'm pretty sure I've got
an ant crawling up me. Eugh!

511
00:39:54,040 --> 00:39:58,960
THC appears to rev up production
of this chemical and this switches
our brain onto high alert.

512
00:40:07,000 --> 00:40:09,120
What was that? Was that a train?

513
00:40:09,120 --> 00:40:10,920
I think it was a bear. A bear?

514
00:40:10,920 --> 00:40:15,440
This can make things seem more
meaningful than they are.

515
00:40:15,440 --> 00:40:18,440
'Because of the increased level
of this brain chemical,'

516
00:40:18,440 --> 00:40:21,280
someone's face might
suddenly seem really important

517
00:40:21,280 --> 00:40:23,720
and stand out at you.
And then, you come up with

518
00:40:23,720 --> 00:40:25,600
an explanation for why that this is.

519
00:40:25,600 --> 00:40:29,640
And that might be, "That person
is watching me, this person
is looking at me."

520
00:40:29,640 --> 00:40:32,280
Gradually, this develops
into a kind of paranoia.

521
00:40:32,280 --> 00:40:33,880
"This person hates me."

522
00:40:33,880 --> 00:40:39,040
There's just bugs everywhere.
There are horrible massive ants,
look at them.

523
00:40:41,000 --> 00:40:45,000
Whoa. What? Do you reckon
there's adders in the grass?

524
00:40:45,000 --> 00:40:49,920
In extreme cases, people start seeing
and hearing things that aren't there.

525
00:40:49,920 --> 00:40:52,640
There's loads
of jumping spiders everywhere.

526
00:40:54,160 --> 00:40:57,960
In fact, an estimated one in ten
cannabis users will experience bouts

527
00:40:57,960 --> 00:41:02,160
of hallucinations,
anxiety and paranoia.

528
00:41:02,160 --> 00:41:08,280
Scientists suspect a vulnerability to
psychosis could be, in part, genetic.

529
00:41:08,280 --> 00:41:13,280
'It would be great if we could go
to a music festival'

530
00:41:13,280 --> 00:41:19,200
and have a little tent at the
entrance and do a little stab on
everybody's thumb as they came in.

531
00:41:19,200 --> 00:41:21,440
And, an hour later,
be able to tell them,

532
00:41:21,440 --> 00:41:24,800
"You have the genes which make
you vulnerable to going psychotic

533
00:41:24,800 --> 00:41:28,520
"after taking cannabis and therefore
you should avoid it at all costs."

534
00:41:28,520 --> 00:41:32,120
And then the other 90%
of the population, say, "You're OK,

535
00:41:32,120 --> 00:41:35,440
"don't worry about it, you can
smoke cannabis for the weekend."

536
00:41:35,440 --> 00:41:38,400
We're not at that stage yet.

537
00:41:38,400 --> 00:41:43,200
So, for a small percentage
of the population, getting high
is something of a lottery.

538
00:41:44,680 --> 00:41:47,840
For very young smokers,
it's more like Russian roulette.

539
00:41:49,920 --> 00:41:53,800
People who start smoking before 15
seem to have a much greater risk

540
00:41:53,800 --> 00:41:59,480
of developing the harmful effects
from smoking the drug - things like
psychosis and memory impairment.

541
00:41:59,480 --> 00:42:04,680
It could be the brain is still
developing in adolescence.

542
00:42:04,680 --> 00:42:09,120
And maybe, if you throw a lot of
cannabis at your brain when your

543
00:42:09,120 --> 00:42:14,680
neural systems are still developing,
it may cause some wiring changes
from which you may not recover.

544
00:42:15,640 --> 00:42:22,080
So, cannabis is a bad idea
for anyone under the age of 15,
or with a vulnerability to psychosis.

545
00:42:24,240 --> 00:42:29,160
But it now appears even people
with no history of mental illness
can have a bad trip with skunk,

546
00:42:29,160 --> 00:42:33,960
like this student who, to protect
her future job prospects,
wants to be known as Catherine.

547
00:42:33,960 --> 00:42:38,480
With normal weed, if I'm happy
and having a good time with
the right people, it's great.

548
00:42:38,480 --> 00:42:42,600
But with skunk, if I'm on a low ebb,
if I've got not much energy,

549
00:42:42,600 --> 00:42:50,200
I'm likely to sink into a low
energy-less, enthusiasm-less pit.

550
00:42:50,200 --> 00:42:56,840
She's 19 and only gets high
a couple of times a week -
and prefers not to smoke skunk.

551
00:42:59,960 --> 00:43:03,440
Dr Celia Morgan and her team
from UCL have so far visited

552
00:43:03,440 --> 00:43:06,920
the homes of 450 smokers,
like Catherine.

553
00:43:06,920 --> 00:43:09,760
'There are so many young
people that smoke cannabis.'

554
00:43:09,760 --> 00:43:13,920
Whilst it's only a small number
that experience these kinds
of harms from them,

555
00:43:13,920 --> 00:43:19,840
if we can identify what makes people
vulnerable to these harms, then we
can protect these people from them.

556
00:43:21,600 --> 00:43:27,120
At UCL, they're approaching
the link between cannabis and
psychosis from a whole new angle,

557
00:43:27,120 --> 00:43:32,600
by looking, not at the genetic
make-up of the person, but at the
composition of the plant itself.

558
00:43:36,360 --> 00:43:41,640
The second most active ingredient
after THC is cannabidiol, or CBD.

559
00:43:45,000 --> 00:43:51,240
It grows alongside the THC in tiny
bubbles of resin, but it's present
in only small quantities in skunk.

560
00:43:52,240 --> 00:43:58,720
Growing cannabis under 24-hour
lighting seems to increase the THC
content and reduce the CBD content.

561
00:43:59,760 --> 00:44:04,760
And research shows that CBD might
counter some of THC's ill effects.

562
00:44:06,680 --> 00:44:13,840
So Dr Morgan wants to see if CBD
might be powerful enough to reduce
the risk of a bad trip.

563
00:44:13,840 --> 00:44:15,880
I might need all of that.

564
00:44:15,880 --> 00:44:21,800
The first step is to take
a sample of Catherine's weed,
to test later for CBD levels.

565
00:44:21,800 --> 00:44:25,920
How would you describe that type
of cannabis? It's Thai weed.

566
00:44:28,160 --> 00:44:32,720
Catherine is then asked to
go outside and get high,
like she normally she does.

567
00:44:39,120 --> 00:44:42,200
I think probably one of
the best experiences is that

568
00:44:42,200 --> 00:44:46,680
myself and one of my best friend
will have heart to hearts

569
00:44:46,680 --> 00:44:49,080
and get emotionally close.

570
00:44:50,120 --> 00:44:55,640
And that's just part of the
process in smoking a joint -
to chill out, unwind, offload.

571
00:45:01,200 --> 00:45:03,520
Now she's ready to start the test.

572
00:45:05,760 --> 00:45:08,440
How are you feeling?
Do you feel stoned?

573
00:45:08,880 --> 00:45:12,680
I want to you to say how much
these describe your experience
right now.

574
00:45:14,000 --> 00:45:20,920
On a scale of nought, not at all,
one, slightly, two, moderately,
and three, strongly.

575
00:45:20,920 --> 00:45:23,640
Dr Morgan wants to see
what's happening to her mood.

576
00:45:23,640 --> 00:45:26,960
She's looking out for any signs
of extreme anxiety or paranoia.

577
00:45:26,960 --> 00:45:30,840
Your mood is going
up and down a lot? Two.

578
00:45:30,840 --> 00:45:34,320
You feel that you can predict
what is about to happen? Two.

579
00:45:34,320 --> 00:45:39,720
You think people are saying
or doing things to annoy you? One.

580
00:45:39,720 --> 00:45:43,840
You find it more difficult
than usual to start doing things?

581
00:45:43,840 --> 00:45:45,520
Two!

582
00:45:46,720 --> 00:45:51,760
'So, Catherine had some thought
disorders, things like not being
able to follow conversations,'

583
00:45:51,760 --> 00:45:54,200
having a lot of thoughts at once.

584
00:45:54,200 --> 00:45:58,880
But she didn't show very many
perceptual disturbances or paranoia.

585
00:45:58,880 --> 00:46:02,040
The next step
is to test what's in her drugs...

586
00:46:04,400 --> 00:46:11,080
..in particular, the amount of
mind-altering THC in her cannabis,
as compared to the more mellow CBD.

587
00:46:12,160 --> 00:46:14,160
So this is quite interesting.

588
00:46:14,160 --> 00:46:19,960
Catherine's cannabis contained about
7% THC, which is an average level.

589
00:46:19,960 --> 00:46:25,120
But it also contained what we would
call a high level of CBD, 0.4%.

590
00:46:25,120 --> 00:46:28,720
So it seems to be offsetting
some of the effects of THC.

591
00:46:30,640 --> 00:46:37,240
The next stage is to bring
Catherine into the lab, to give
her pure THC, with no CBD.

592
00:46:38,880 --> 00:46:42,320
This is the lab equivalent of skunk.

593
00:46:42,320 --> 00:46:45,080
Ten. And breathe out
as slowly as you can.

594
00:46:49,280 --> 00:46:51,840
It gets you there.
It's quite tickly.

595
00:46:51,840 --> 00:46:55,200
Probably need some water in a mo.
I'll go and get you some. Cheers.

596
00:47:00,080 --> 00:47:04,200
Once inside Catherine's blood,
the THC travels up to her brain

597
00:47:04,200 --> 00:47:07,120
and, within five minutes,
she starts to react.

598
00:47:10,160 --> 00:47:14,760
Are you hearing sounds
or having visions that you think
others are not able to see? Yeah.

599
00:47:14,760 --> 00:47:16,880
Yeah. What sort of thing?

600
00:47:16,880 --> 00:47:21,080
Um, I feel, like,

601
00:47:21,080 --> 00:47:24,920
um, parallel to this situation.

602
00:47:24,920 --> 00:47:29,240
There's another situation going on,
which is a dream.

603
00:47:29,240 --> 00:47:32,440
She's experiencing
a disconnection with reality.

604
00:47:32,440 --> 00:47:37,280
Have you been receiving any special
messages from people or from the way
things are arranged around you?

605
00:47:37,280 --> 00:47:40,120
Yes. What sorts of messages?

606
00:47:40,120 --> 00:47:43,880
I feel like I've got some sort
of communication going on,

607
00:47:43,880 --> 00:47:47,720
like a conversation
with my boyfriend. Oh, really?

608
00:47:47,720 --> 00:47:49,680
Yeah, parallel to this one.

609
00:47:49,680 --> 00:47:53,200
Some sort of telepathic
type communication? Yeah.

610
00:47:54,440 --> 00:47:56,080
And how does that make you feel?

611
00:47:56,080 --> 00:47:57,960
Special. Special, OK.

612
00:47:57,960 --> 00:48:00,400
'So Catherine had,
what we would say,'

613
00:48:00,400 --> 00:48:04,120
was an actual psychotic reaction,
so she thought she could communicate

614
00:48:04,120 --> 00:48:06,520
telepathically with her boyfriend.

615
00:48:06,520 --> 00:48:10,480
She thought
she was simultaneously
experiencing two different realities.

616
00:48:10,480 --> 00:48:12,960
Do you think you're
being talked about? Three.

617
00:48:12,960 --> 00:48:18,680
You're experiencing something
very special or important? Three.

618
00:48:18,680 --> 00:48:22,240
Before long, paranoia creeps in.

619
00:48:22,240 --> 00:48:26,000
Celia, could I just stop you,
while I'm having this thought?

620
00:48:26,000 --> 00:48:29,720
The reason I'm saying "three"
to these statements is because

621
00:48:29,720 --> 00:48:32,640
when you say them,
they go into my head and it happens.

622
00:48:32,640 --> 00:48:36,120
Do you want to stop?
Are you all right?

623
00:48:36,120 --> 00:48:39,960
I don't mind go on,
but I just think it would be
scientifically inaccurate,

624
00:48:39,960 --> 00:48:43,280
because it's like planting a thought
there and then I say "yeah".

625
00:48:43,280 --> 00:48:46,280
'What we saw was a classic example
of how some people'

626
00:48:46,280 --> 00:48:48,800
are more vulnerable to the
effects of THC than others.

627
00:48:50,320 --> 00:48:54,400
But, when she smoked non-skunk weed
at home, the CBD in it appeared

628
00:48:54,400 --> 00:48:57,120
to counteract some
of these ill effects.

629
00:48:57,120 --> 00:49:02,560
One of our aims is that, if people
are going to smoke cannabis,
we'd strongly advise them to smoke

630
00:49:02,560 --> 00:49:08,040
strains like hash and normal weed,
rather than things like skunk,
with a much higher THC content.

631
00:49:08,040 --> 00:49:12,200
So, here in the UK, cannabis
comes with serious health warnings

632
00:49:12,200 --> 00:49:15,680
and a possible prison sentence
of up to five years for possession.

633
00:49:16,640 --> 00:49:20,600
But, in some parts of the United
States, it's a whole different story.

634
00:49:20,600 --> 00:49:24,320
Marijuana is being touted
as a wonder drug -

635
00:49:24,320 --> 00:49:27,920
a potential cure-all
for any number of conditions.

636
00:49:27,920 --> 00:49:31,200
RADIO: Hello, I'm Dr Greenthumb.
Have you ever had the problem

637
00:49:31,200 --> 00:49:34,160
of running out of weed
and just can't find some anywhere?

638
00:49:37,280 --> 00:49:39,880
Right this way,
to see the Cush Doctor today.

639
00:49:41,000 --> 00:49:44,640
Welcome to California...
The doctor is in.

640
00:49:44,640 --> 00:49:48,440
..one of 15 states where
"medical" marijuana is now legal.

641
00:49:49,840 --> 00:49:53,400
I use medical marijuana for anxiety,
neck pain and back pain.

642
00:49:53,400 --> 00:49:55,080
I have a torn ligament in my knee.

643
00:49:55,080 --> 00:50:00,960
Doctors routinely prescribe it
for depression, to stimulate
the appetite of AIDS patients,

644
00:50:00,960 --> 00:50:04,720
to help people sleep -
and even for writer's block.

645
00:50:06,800 --> 00:50:10,520
TV: Medical marijuana stores have
been sprouting like weeds in LA.

646
00:50:10,520 --> 00:50:16,720
Here in Los Angeles, there are
currently more cannabis dispensaries
than there are Starbucks.

647
00:50:16,720 --> 00:50:21,920
Cookies, two or three
different kinds of cookies. Pies.

648
00:50:21,920 --> 00:50:23,280
Chocolate milk, also.

649
00:50:25,320 --> 00:50:28,880
No surprise that cannabis is now
the number one cash crop in America.

650
00:50:28,880 --> 00:50:30,400
He-he-he! Check it out, man.

651
00:50:30,400 --> 00:50:33,600
But critics say
it is too easy to get.

652
00:50:33,600 --> 00:50:38,960
The compassionate use is sort
of being abused by people that
would seek out recreational use.

653
00:50:40,120 --> 00:50:44,280
RADIO: Thanks, Dr Green.
# Doctor. #

654
00:50:44,280 --> 00:50:50,160
Back in the UK,
there's no sign of any cannabis
dispensaries on the high street.

655
00:50:51,720 --> 00:50:55,560
That's because the law
makes no distinction
between supplying cannabis

656
00:50:55,560 --> 00:51:01,760
for recreational reasons, versus
medical ones. Both carry a maximum
prison sentence of 14 years.

657
00:51:04,760 --> 00:51:08,200
18-year-old Hannah
works in a nursing home.

658
00:51:08,200 --> 00:51:13,640
Her mum Teresa is one of the 100,000
people in the UK who suffers
from multiple sclerosis.

659
00:51:15,160 --> 00:51:19,360
'She got her first bout of
her MS years and years ago,

660
00:51:19,360 --> 00:51:21,840
'but they didn't realise
it was MS at the time.'

661
00:51:21,840 --> 00:51:24,000
It took about two years for her
to finally

662
00:51:24,000 --> 00:51:26,040
get diagnosed with it,
when I was about eleven.

663
00:51:30,760 --> 00:51:34,560
The MS is causing Teresa's body
to attack her own nervous system.

664
00:51:37,160 --> 00:51:42,000
Too many messages are being
fired from her brain to her legs,

665
00:51:42,000 --> 00:51:45,200
which causes her leg muscles
to seize up in painful cramps.

666
00:51:46,720 --> 00:51:51,280
It's like someone's got
a tourniquet round your leg
and then, as you walk,

667
00:51:51,280 --> 00:51:54,560
that tourniquet starts
to cramp down, until such time

668
00:51:54,560 --> 00:51:58,400
as you don't know how to pick one
foot off the floor to keep walking. 

669
00:51:58,400 --> 00:52:04,800
About 30% of MS sufferers
report that smoking cannabis
helps with their symptoms.

670
00:52:09,840 --> 00:52:11,360
But Teresa is a mum.

671
00:52:11,360 --> 00:52:14,280
She's never broken a law in her life.

672
00:52:15,560 --> 00:52:20,840
My mum gave me the normal parent
drug speech, probably when I went to
high school, so about ten years old.

673
00:52:20,840 --> 00:52:25,680
But it was the normal "Be sensible,
it can ruin your life", etc, etc.

674
00:52:28,840 --> 00:52:29,880
That's very kind.

675
00:52:29,880 --> 00:52:32,960
You've got a smile,
that's what you've got.

676
00:52:32,960 --> 00:52:36,760
'I've never taken any kind
of recreational drugs.'

677
00:52:36,760 --> 00:52:40,280
I don't really understand what
"high" is, but my head is always,

678
00:52:40,280 --> 00:52:44,000
it's not up there in the clouds,
it's kind of down here with me.

679
00:52:45,040 --> 00:52:48,040
Now she's about to take
a hit of cannabis

680
00:52:48,040 --> 00:52:50,400
in the middle
of a Norfolk high street.

681
00:52:51,600 --> 00:52:54,120
This is Britain's answer
to medical marijuana.

682
00:52:54,120 --> 00:52:57,720
It's a spray called Sativex,
that's now legal.

683
00:53:00,600 --> 00:53:03,320
She sprays the drug into her mouth.

684
00:53:03,320 --> 00:53:07,600
It's specially designed to get
absorbed into her bloodstream
through her throat.

685
00:53:07,600 --> 00:53:14,480
The drug travels straight to her
brain, where it starts slowing down
the messages being fired at her legs.

686
00:53:14,480 --> 00:53:18,680
Her leg muscles begin to relax.

687
00:53:22,040 --> 00:53:26,760
For the last four years,
Hannah has brought her mum
to see Dr William Notcutt,

688
00:53:26,760 --> 00:53:31,400
who has been conducting one of the
few legal marijuana trials in the UK.

689
00:53:31,400 --> 00:53:32,560
OK, thanks very much.

690
00:53:32,560 --> 00:53:38,840
'Teresa is a typical example of the
benefits of cannabis to a patient.'

691
00:53:40,120 --> 00:53:44,680
This isn't a wonder drug.
It's not a miracle cure for MS,

692
00:53:44,680 --> 00:53:47,480
or for control of the symptoms.

693
00:53:47,480 --> 00:53:52,720
But many patients do not get benefit
from the existing drugs,

694
00:53:52,720 --> 00:53:57,040
so this gives us another
very useful, safe drug,

695
00:53:57,040 --> 00:54:00,320
which has a potential
for helping a lot of patients.

696
00:54:00,320 --> 00:54:03,200
So, off you go.
Let's see how you can walk.

697
00:54:09,200 --> 00:54:14,520
Cannabis is a unique plant
that has the power to change
our consciousness.

698
00:54:14,520 --> 00:54:20,960
To some,
it's a valuable medicine that has
been overlooked for too long.

699
00:54:20,960 --> 00:54:24,440
For others,
it's a harmless pastime.

700
00:54:25,960 --> 00:54:29,800
Mike had no problem
quitting while he was revising.

701
00:54:29,800 --> 00:54:34,120
He needs three As in order to
go to his university of choice.

702
00:54:35,880 --> 00:54:41,680
I got two A stars and an A, so I'm
very pleased with myself today.

703
00:54:41,680 --> 00:54:47,960
I think it's definitely against
the stereotype that people who
smoke weed are like dropouts.

704
00:54:49,160 --> 00:54:53,680
But not everyone can share
Mike's casual approach to cannabis.

705
00:54:53,680 --> 00:54:58,080
I'm at a bit of a crossroads. I'm
having a bit of a mid-youth crisis.

706
00:54:59,600 --> 00:55:04,160
I'd like to go to uni and study
pharmacology or something like that,

707
00:55:04,160 --> 00:55:08,080
but I know that I'm not good enough
at science to be able to do that,

708
00:55:08,080 --> 00:55:11,560
so I want to do something
a bit different, I don't know what.

709
00:55:11,560 --> 00:55:15,840
Books and socks.
Perfect combination.

710
00:55:15,840 --> 00:55:18,600
It definitely makes
me less organised,

711
00:55:18,600 --> 00:55:20,840
but then you've got to
balance it out.

712
00:55:20,840 --> 00:55:22,480
Like the state I was in earlier,

713
00:55:22,480 --> 00:55:29,000
would I have brought it all in here
and done it properly, or would
I have just panicked and done bits

714
00:55:29,000 --> 00:55:31,640
and then had
a nervous breakdown and cried?

715
00:55:33,000 --> 00:55:34,120
Oh.

716
00:55:34,120 --> 00:55:39,200
But, whereas Imogen finds cannabis
a fun antidote to stress...
That feels good.

717
00:55:39,200 --> 00:55:43,800
..for some,
the high eventually turns to a low.

718
00:55:45,800 --> 00:55:47,360
'Good afternoon, Lifeline!'

719
00:55:47,360 --> 00:55:49,600
Yeah, hi,
I'm wondering if you can help me.

720
00:55:49,600 --> 00:55:56,600
I smoke cannabis and stuff
like that and I really want
to get off cannabis now.

721
00:55:56,600 --> 00:56:00,400
Chris has decided he needs help, if
he's going to move on with his life.

722
00:56:00,400 --> 00:56:01,520
Thanks. Bye.

723
00:56:06,400 --> 00:56:09,560
But, in the end,
for even the most committed stoner,

724
00:56:09,560 --> 00:56:14,280
the ultimate chill-out drug might
prove too effective for its own good.

725
00:56:14,280 --> 00:56:18,080
If everyone in the world
smoked weed,

726
00:56:18,080 --> 00:56:23,360
the world would be an awesome place,
it would be a lot more chilled out.

727
00:56:23,360 --> 00:56:27,400
People wouldn't start wars.
But maybe no-one would
get anything done? Yeah.

728
00:56:49,040 --> 00:56:52,080
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729
00:56:52,080 --> 00:56:55,120
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