Johnny Stack was just 19 when he jumped off a car park in Colorado. He thought he could fly. His mum Laura found out later that he’d been seeing things that weren’t there, hearing voices, thinking the Russian mob was after him. All because of weed.

This isn’t the story most people expect about cannabis. Johnny wasn’t some street junkie. He was clever – got perfect scores in his maths exams. He played guitar, ran cross country, had everything going for him. Until high potency cannabis changed everything.

The Weed That’s Nothing Like the Old Days

Here’s what most people don’t know: the weed today is completely different from what people smoked back in the 60s and 70s. Back then, it had about 2% THC – that’s the stuff that gets you high. Now? Some of these high potency cannabis products have nearly 100% THC.

Grace, Johnny’s friend from university, shows off the gear that’s normal now. “This one’s 90% THC,” she says, holding up what looks like a normal cigarette. “You can grab this stuff at a gas station.”

Think about that for a minute. You can buy something at a petrol station that’s 45 times stronger than what hippies were smoking at Woodstock. These high THC cannabis products are everywhere, and kids think they’re safe because they’re legal.

What Really Happens in Your Brain

Dr Amanda works in a Colorado hospital emergency room. She sees the results every single day. “People think marijuana psychosis is rare,” she says. “It’s not. It’s huge. And we’re going to see even more as more kids use.”

When you smoke modern weed, especially the strong stuff, it floods your brain with chemicals. Your brain normally makes these chemicals naturally to help you cope with life. But when you dump massive amounts in from outside, it messes everything up.

The scary bit? Unlike alcohol that your body can get rid of in hours, high potency cannabis sticks around in your brain for weeks or months. Especially in teenagers whose brains are still growing.

Johnny’s Story: How It All Went Wrong

Johnny first tried weed at 14 at a school party. His parents found out and told him never to do it again. But like lots of kids, he kept using in secret.

When he turned 18, something changed. Johnny got a medical marijuana card. His mum Laura is still angry about this: “He was totally healthy. There were no chronic conditions. It’s a complete farce.”

That’s when things got really bad with the high THC cannabis he could now access legally. Laura describes what happened to her son: “It was like an alien came and took my child and put another one there. Johnny was always loving and warm and funny, and this one was mean and toxic and rude.”

Johnny started getting paranoid. He thought people were following him. He heard voices. One night, he called his friend Grace in a panic, sleeping rough in Denver because he was so scared of imaginary threats.

When High Strength Cannabis Takes Over

The medical term is cannabis-induced psychosis, but what it really means is terrifying. People see things that aren’t there. They hear voices. They become violent. Sometimes they hurt themselves or others.

Bryn’s story shows how quickly high potency cannabis can destroy a life. She was 26, had a good job as an audiologist, never really smoked much weed. One evening, she tried some of her boyfriend Chad’s high-strength cannabis.

Within minutes, she was hallucinating, seeing her own dead body, watching horrible things happen on an imaginary TV screen. She ended up stabbing Chad 108 times and her own dog. Chad died. Bryn nearly died too.

“I never had psychosis before this or after this,” Bryn says. “I never had any mental illness before this and after this.”

The Numbers Don’t Lie

Here’s the bit that should scare every parent: nearly half of people who get cannabis-induced psychosis from high THC cannabis go on to develop serious mental illness like schizophrenia. And it’s not just people with existing problems – it can happen to anyone.

In Colorado, suicide is the biggest killer of young people aged 15-18. And the number one drug they find in these kids’ systems? THC.

Emergency rooms see something called “scromiting” now – that’s screaming and vomiting at the same time from people who’ve used too much cannabis. Dr Amanda sees at least one case every day.

The Industry Doesn’t Want You to Know

When Colorado tried to put limits on how strong weed products could be, the high potency cannabis industry fought back hard. They’ve got serious money now – over $40 billion worth. Big tobacco companies like the ones that make cigarettes are getting involved.

Sound familiar? It should. The tobacco companies spent decades telling everyone cigarettes were safe, even healthy. Doctors recommended them. Now we know cigarettes kill more people than any other preventable cause.

Laura Stack, Johnny’s mum, sees the same pattern: “This is going to be big tobacco all over again.”

Johnny’s Final Days

Even after everything, Johnny had moments where he got better. When he stopped using high potency cannabis and took medication for his psychosis, he became himself again. “It was like aliens brought him back,” his mum says.

But cannabis-induced psychosis is tricky. People feel better and think they can use again safely. Johnny kept going back to high THC cannabis, and each time the psychosis got worse.

Three days before he died, Johnny wrote in his journal that the mob was after him. He spent 20 minutes in that car park before he jumped. His phone had a photo he’d taken of his car’s odometer – 133661 – with a message about Newton’s laws of physics.

The coroner ruled it suicide, but Laura knows the real cause: “We’re so angry that this poison was available to him.”

What Parents Need to Watch For

If your teenager is using cannabis, here’s what to look out for:

• Sudden personality changes
• Paranoid thoughts – thinking people are following them or plotting against them
• Hearing voices or seeing things
• Becoming violent or aggressive
• Staying awake for days or sleeping all the time
• Dropping out of activities they used to love

Don’t think it won’t happen to your kid because they’re smart or come from a good family. Johnny had everything going for him too. The danger comes from today’s high potency cannabis, not the person using it.

Grace’s Recovery

Grace, Johnny’s friend, kept smoking after he died. “I wanted to get super high,” she says. “Grieving was really difficult.”

It took her years to realise how sick she’d become. The paranoia Johnny had developed? Grace got it too, and it never went away even after she stopped smoking.

She’s been clean for two years now. She takes medication and sees a therapist. “I think a lot clearer now,” she says. But she knows she’ll need treatment for the rest of her life.

“I know it wouldn’t have been this bad” without the weed, she says.

A Mum’s Mission

After Johnny died, Laura could have just grieved quietly. Instead, she started Johnny’s Ambassadors, visiting schools to tell his story. She’s spoken to thousands of kids and parents.

“I can either sit here in my bed for the rest of my life and cry, or I can do something about it,” she says.

Her work helped change some laws in Colorado. Now when people buy high strength cannabis, they get warnings about mental health risks. It’s not enough, but it’s a start.

What We All Need to Know

This isn’t about being anti-drug or trying to scare people. It’s about being honest. The high potency cannabis being sold now isn’t the gentle stuff from the past. It’s strong enough to cause serious mental health problems, especially in young people.

Cannabis-induced psychosis is real. It’s happening to thousands of families. And most people have no idea it’s even possible.

If you’re thinking about trying cannabis, or your kids are, please learn about what you’re really dealing with. Ask questions. Look at the THC levels. Understand the risks from high THC cannabis.

Johnny’s death was preventable. So are the ones that might come next.

Source: PBS