LIZ HAYES: Back in the ’30s, there was a melodramatic little propaganda film called Reefer Madness. In no uncertain terms, it thundered on about the evils of the demon weed, that mind-destroying drug marijuana. Naturally enough, hip youngsters thought it was hilarious. They still do. But, as it turns out, reefer madness is no laughing matter. It really does exist. Wait until you see the latest, the most comprehensive research. It proves cannabis really can cause psychosis, can wreck young brains. Not only that, the drug itself is now stronger, super strong, and the users are younger, much younger – 10 and 11 years old.
LIZ HAYES: Dope, weed, pot – call it what you want, but smoking cannabis has been considered a rite of passage for generations. But that might have to change because this drug is much stronger and more dangerous than ever before.
PROFESSOR YASMIN HURD: If the concentrations of cannabis continue to rise and the availability of cannabis is how it is, it will definitely have a bigger impact than cocaine or heroin, absolutely
LIZ HAYES: This drug can permanently damage brains?
JULIE LYNN EVANS: Yeah. That I see all the time.
LIZ HAYES: Is there a link between this drug and suicide?
JULIE LYNN EVANS: Oh yes.
LIZ HAYES: Twenty-one-year-old Lachlan Preece has everything to live for. He’s smart, sporty and popular. But three years ago, his life turned to hell. Cannabis sent Lachlan mad. How often would you smoke?
LACHLAN PREECE: Towards the end, it was pretty much every day.
LIZ HAYES: How many times a day?
LACHLAN PREECE: You know, two or three joints a day.
LIZ HAYES: Towards the end of 2002, the dope started altering Lachlan’s mental state. He was becoming manic and delusional, suffering from cannabis psychosis.
LACHLAN PREECE: I felt that, like, everything was just so easy and I could conquer incredible goals and I’d just do it like that.
LIZ HAYES: And then one day, in his bedroom, Lachlan snapped, launching himself into a three-day psychotic bender that would end in a psychiatric ward.
LACHLAN PREECE: I was starting a new life for myself so I had to, you know, just everything had to go, everything, all the old stuff. I just wanted to completely live in the moment and the past just didn’t matter. So I destroyed it all. And yes, smashed this mirror and, you know, blood everywhere. And that’s when my parents came in and saw … I’m just standing here and the room’s, you know, completely trashed … looks like a bomb’s hit it … and there’s just blood everywhere and blood dripping out of my hand. And they came in and I was actually in such a good mood that I was smiling.
SUSAN PREECE: It’s a tiny room but it took me 12 hours to clean it up, he’d done so much damage. And just washing the blood off the walls and things like that was just heart-wrenching for me. I just thought, you know, our lives had been turned upside down.
LIZ HAYES: You must have felt as though you were losing your son.
GORDON PREECE: Yeah, it did seem for a while, like, you do panic and you just wonder, you know, where he’s gone, because you couldn’t get to him.
LACHLAN PREECE: I’d basically just started … didn’t know where I was walking, I just started walking in the direction of the sun. When you are kind of manic and you’re at that point in the psychosis, you just believe that something will come up. You go outside and you go, “I’m just going to walk, something will happen, I don’t know what yet.” For some reason, I thought that there was going to be a massive, massive party being held for me at Rod Laver Arena. I walked to Rod Laver Arena, I think, and just kept walking and kept walking and then I got sidetracked and went to the Yarra. I could see footsteps just stepping in the ground next to me, and even though no-one was there, I, of course, just thought, you know, there was someone there. It’s stuff like that you definitely know is psychosis.
SUSAN PREECE: We were trawling the streets, looking for him in the dark, because we didn’t know where he was. And I just saw him in the middle of a really busy road near us just playing chicken with the traffic. And I look back on those things, thinking, at any point during that 24 hours he could have easily died.
LIZ HAYES: You have no doubt that marijuana played a major role in your psychosis?
LACHLAN PREECE: Yeah, yeah definitely. No doubt at all.
LIZ HAYES: It’s now clear that what was once considered a socially acceptable drug is anything but. And it’s research that’s taking place here in Sweden that shows just how dangerous cannabis can be. We’re now being told that teenagers, in particular, are not only at real risk of a psychiatric illness, but that cannabis can damage their brain for life.
PROFESSOR YASMIN HURD: We have two hemispheres of the brain and cannabis has an effect all over the brain because the receptors where cannabis binds to are located throughout here – our cortex, our cerebellum for motor coordination…
LIZ HAYES: Professor Yasmin Hurd, from Sweden’s Karolinska Institute, is one of the world’s leading brain researchers. She has discovered cannabis can have a profound and lasting impact on the developing teenage brain.
PROFESSOR YASMIN HURD: Early cannabis exposure changes the chemical make-up of the brain and, therefore, how it processes information. And those brain regions that it’s changed in are very important for emotional processing and for the underlying disorders related to psychiatric illnesses such as schizophrenia, drug addiction.
LIZ HAYES: You say the scientific data is there to show that there is a direct link between cannabis and psychosis?
PROFESSOR YASMIN HURD: Definitely. There are studies now worldwide that have shown this. The earlier you use cannabis – and kids now are using it earlier and earlier – the greater the effect on the brain. So it’s cannabis with development.
LIZ HAYES: How young are we talking here?
PROFESSOR YASMIN HURD: You have kids starting at 10, 11 years old.
LIZ HAYES: The adolescent brain is particularly vulnerable. As it matures, indicated here in blue, it becomes hard wired. Cannabis can disturb the chemical balance of the brain, causing psychosis.
JULIE LYNN EVANS: With the skunk, which is 30 to 60 times higher in THC content than the ordinary block or the stuff that was around in the ’60s, people are really hurting their brains, particularly, particularly, the young people, whose brains aren’t properly formed yet.
LIZ HAYES: Julie Lynn Evans is a London-based psychotherapist who is at the front line of what she calls a losing battle. More and more young patients are being sent to her with cannabis-related psychosis. And this is what they’ve been smoking. It’s called skunk, the most potent form of cannabis. Loaded with THC, the component of the drug that gets you high, it’s regarded by a growing number of experts as the most dangerous drug on the streets today.
JULIE LYNN EVANS: I would prefer to have an 18-year-old hooked on heroin to treat, or crack cocaine, than skunk.
LIZ HAYES: That’s an extraordinary thing to say.
JULIE LYNN EVANS: Yes, I know. Very controversial.
LIZ HAYES: That you’d prefer a young person to be hooked on heroin.
JULIE LYNN EVANS: Well, as long as they’re smoking it. I think once they go into needles, that’s a different ball game.
LIZ HAYES: So you don’t recover from skunk?
JULIE LYNN EVANS: A percentage of children, and we don’t know what percentage yet and it’s a small percentage, but because I work on the edge and as a percentage I see don’t recover and there’s nothing that you can do about them.
LIZ HAYES: Lachlan Preece first tried pot at 15, but only smoked it heavily in his final year of school. Within six months, he was delusional.
LACHLAN PREECE: I started thinking I could become invisible and that’s, you know, that’s when people would look at you and go, “Man, like something’s not right.” Like, when you start having … because you just … you kind of elevate and elevate. So I ended up escaping from hospital, invisibly, of course. That’s when I started seeing all the auras and I started thinking it was initiation into heaven, I guess.
LIZ HAYES: It’s party time in Amsterdam, the liberal capital of the Western world. Here, just about anything goes. Cannabis is freely available to be bought and smoked, as long as you’re over 18, of course. So it’s no surprise that it’s in this town you’ll find the drug’s strongest defenders.
KEN JOHNSON: Without hyperbole, it’s the single most important plant in human history. It’s the first thing we cultivated as a crop and the first thing we wove into a cloth and wore on our back that wasn’t an animal skin. It was the only thing strong enough to make paper that would last several generations, it’s the only thing strong enough to rig a ship to sail around the world. So it’s had these places in these fundamental parts of our development.
LIZ HAYES: Ken Johnson runs Amsterdam’s Seed Bank, a mecca for cannabis connoisseurs. Here, you can buy the high you want, the steady trade ample evidence that tourists don’t come here just for the tulips.
KEN JOHNSON: There’s no such thing as a safe drug. Sugar isn’t, and caffeine aren’t safe drugs.
LIZ HAYES: Correct me if I’m wrong, but I think we’re yet to see a sugar user having a psychotic episode. As a direct result.
KEN JOHNSON: Well, we see psychotic episodes … the terminology is often very mis-applied. A psychotic symptom, a psychotic episode, are not the same thing as a psychosis, which is not the same thing as schizophrenia. And as far as science or medicine having decided that cannabis is linked to these things, it’s extremely flimsy evidence.
LORNA CLAY: This is a prime example of a Cannabis Indica variety. It’s actually a Hindu Kush cross with skunk number one. We call it the pot of gold. These originate from colder, more mountainous regions.
LIZ HAYES: Other champions of cannabis, like Lorna Clay, who runs an information service about the drug, point to its medicinal properties. It can be used to treat the symptoms of anything from AIDS to arthritis.
LORNA CLAY: Medically, this is used to treat people who have glaucoma, multiple sclerosis, chronic pain, even arthritis.
LIZ HAYES: But even Lorna expresses concern about the potential effects of cannabis on teenagers. Do you think young people should be smoking marijuana?
LORNA CLAY: No, I don’t at all. That’s also to do with the fact that when you’re young, your brain is not fully matured until you’re 18 to 21 years old.
PROFESSOR YASMIN HURD: There is definitely evidence out there in many studies now, worldwide, to show a link between cannabis and especially, I want to emphasise, early cannabis exposure and schizophrenia.
LIZ HAYES: If you needed further proof illustrating the potentially lethal mix of teenagers and cannabis, it can be found here in Professor Hurd’s lab. Young rats exposed to cannabis developed an appetite for other drugs. It’s called the gateway theory.
PROFESSOR YASMIN HURD: We did an animal study where we gave cannabis during the adolescent period and then studied them as adults, and the group of rats that had gotten THC, the active component of cannabis, as teenagers, they took more heroin as adults. So clearly, there was a gateway effect on the neurobiological level that had nothing to do with their friends, their parents, their genetics.
LIZ HAYES: Of course, humans aren’t rats. But we are talking about the vulnerability of our teenagers to an insidious drug. For Lachlan, it took a good 18 months of therapy at Melbourne’s Origin Centre for Adolescent Health and the support of family and friends to help him get back his life. Why do you choose to speak out?
LACHLAN PREECE: Um, I choose to speak out because I think there’s a real lack of communication about it – in terms of marijuana and in terms of the link to mental illness.
LIZ HAYES: What impact has this had upon your life?
LACHLAN PREECE: Um, it’s had a huge, huge impact. I think, I think if anything, it’s made me a lot stronger.
LIZ HAYES: You survived.
LACHLAN PREECE: Yeah, I did survive. Yeah.
LIZ HAYES: Not everyone does.
LACHLAN PREECE: Yeah, I know, I know.