Henry Kwan, 17, fell to his death at his home in Killara after taking a synthetic hallucinogen that was sold to him as LSD. Neighbours hear this bizarre phrase ringing out from the balcony. At first, they don't associate the deep voice with Tom: it sounds almost Satanic. In the darkness, they can faintly see a figure pacing back and forth. They call out, asking if he's all right. Well-known as an early morning runner, and well-liked as a trusted babysitter to several families in this quiet, affluent neighbourhood in Sydney's north where he's spent most of his life, Tom is clearly not himself. The family cats are howling, too, apparently as disturbed by his behaviour as the onlookers. From the balcony, Tom scampers up onto the tiled roof, but loses his footing. A round, wooden table in the front yard breaks his fall not far from the edge of the swimming pool. The force of his weight smashes the furniture to pieces but he miraculously avoids serious injury. A concerned neighbour rings 000. Tom may be bleeding, but he's still got the speed of a cross-country athlete and seemingly superhuman strength, despite his reed-thin frame. He rushes back inside his house, tracking blood through different rooms, before smashing a back fence then running onto the street again, tearing off his clothes. What happens over the next hour or so – Tom breaking a window of a neighbour's house, neighbours chasing him, making him even more paranoid and fearful – is a blur. He winds up several streets from home, lying naked in the middle of the road, surrounded by people looking down at him, including two female police officers and paramedics. It takes a few of them to handcuff him. Hovering not far away is a television news crew, which has received a tip-off about the disturbance. Tom is at risk of having the worst moment of his life spread over the news, but the police are able to keep the media at bay because he's a minor. All the while, Tom continues to ramble incoherently: "The universe is against us! The universe is against us!"

At the fund-raising dinner which his parents are attending, Karl is perplexed when his phone begins to vibrate during a speech. Jasmine also grabs her phone, which is lighting up with messages from five different neighbours asking her to call them immediately. The couple hurriedly excuse themselves before Jasmine calls a trusted friend. "Tom's all right," she's told. "But you need to go straight to the hospital." On arrival around midnight, they're greeted by a sight that haunts all parents: their teenage son unconscious in a hospital bed, covered in dried blood, with plastic tubes snaking out of his mouth and nose. The outlines of this troubling story were sketched by Jasmine, who emailed me after reading a Good Weekend story of mine from June 3, in which I described my own (largely positive) experience with LSD. "LSD is like a monster in our house, sucking all the potential and opportunity out of my beautiful son… as well as creating massive stress for the entire family," Jasmine wrote. "Let me tell you from my experience (and by the way, I am no LSD virgin), that for our precious kids, LSD is plain playing with fire. They can't evaluate the high levels of risk versus the perceived mind 'expanding' benefits, and they are basically ending up, for want of a better word, completely f...ed." Her email led to me knocking on the door of a beautiful family home on a quiet street in Sydney's north where Jasmine and Karl live with Tom and their other child. Clouds of fear and anxiety wash across Jasmine's face as she describes that phone call to her panicked neighbour and the rushed drive to hospital, not yet knowing what she will find on arrival. I can see the embarrassment and regret that Tom relives when telling this story, as he frequently breaks eye contact and looks down at his hands. When the family's black cat leaps onto the table between us, the pair enjoy the distraction from a difficult conversation. The cat purrs contentedly in Jasmine's lap as mother and son stroke its dark fur. But most strikingly of all, what I see inside their home is a clear communication channel between mother and son. Up for frank discussion is a subject that every parent must eventually turn their mind to as they watch their helpless babies grow into confident adolescents: drug use, with all its potential for life-affirming highs or lifealtering pitfalls. Sometimes, the gap between those two possible outcomes is very small indeed. It can be measured in micrograms, and in the marked difference between taking two acid tabs or four. LSD is like a monster in our house, sucking all the potential and opportunity out of my beautiful son. Jasmine, Sydney mother

In the weeks leading up to his decision to take LSD home alone that night, Tom was feeling isolated. He had started at a new school that year, and was still searching for his tribe. "My social life wasn't going heaps well, and I was feeling lonely," he reflects. "If I had better friends, I wouldn't have been thinking about this stuff as much. I was thinking, 'Okay, social stuff's not going so well: why don't I explore this kind of stuff?' " He had smoked a lot of cannabis in 2016, and left his previous school after an incident involving it; mother and son are both cagey about the specifics, but hint at a "naughty group of friends" with whom Tom now rarely associates. Last year, after the cannabis incident at school, Jasmine and Tom began attending the Sydney Drug Education and Counselling Centre (SDECC) in Manly. There, in one-on-one counselling for the son, and group sessions for his mother alongside other parents whose children have demonstrated problematic drug use, the two of them began to learn a new language. For confidentiality reasons, SDECC's counsellors were unable to talk to Jasmine about what Tom disclosed. She learnt that she needed to remove the safety net of parental concern, and allow her son to make up his own mind about why he used cannabis and whether his usage had become an issue. Tom quickly came to trust his counsellor after it became clear that her room was a non-judgmental space where he could talk frankly without the need to guard or withhold his true feelings. People of all ages use drugs because they foresee a positive outcome once a particular substance enters their body. Caffeine and alcohol are largely used for their pleasurable effects, and the same is true for those who seek highs from the likes of cannabis and LSD. In the throes of adolescent experimentation, Tom sought to push the boundaries of his psyche that night by taking a double dose. "Why did you want to do double?" Jasmine asks.

Tom pauses and looks away. "Umm … basically, you go … it's just a lot more intense," he says, as his eyes meet his mother's. "You go deeper, I guess." "You assumed you would, because you'd never tried four before, had you?" she queries. "No," her son replies. "But obviously it's going to be more intense, because it's a bigger dose." Tom says he was searching for something he'd read about on online forums and seen experienced psychedelic drug users describe on YouTube: "ego death", as it's known, occurs when the mind becomes so affected by a mood-altering drug that the user's sense of self, of identity, disappears. "You" no longer exist. The teenager found what he was looking for, but also discovered that its effects were deeply unpleasant. "What made me freak out so much on the come-up was that I started questioning my name: 'Who am I?' I actually forgot my name. I forgot all my friends. I remember …" He pauses and sighs, trying to find the right words. "My room just looked completely foreign. My room's my most familiar thing; I spend a lot of time in there, but it just looked totally, totally foreign, because of the visuals and stuff." Seeking out ego death is a risky prospect because of the possibility that the individual may be unable to reassemble their identity once the effects of the drug wear off – which usually occurs within 12 hours on LSD, though the duration increases in parallel with dosage. What was intended as a temporary unravelling can become permanent, and the individual's perception of reality can be altered for the rest of their life. No matter how experienced the LSD user, there is always the possibility – however small – that one trip can change the trajectory of a life by inducing a psychosis or mental disorder that was previously dormant.

Once it became clear that Tom was safe and sound, if deeply embarrassed and regretful, Jasmine found that some local parents managed to beam a few shafts of sunlight through the dark clouds that had engulfed her family. "On the night of the incident, the entire neighbourhood was involved," she reflects. "Everybody's been really good and upfront, and people were very accepting. Some of them told me, 'This is a rite of passage, it's what kids do, we did it, too.' " She pauses, then cracks a smile. "They also told me, 'Everybody knows, you don't do it at night! What was he thinking, doing it at night?!' " For Tom, that night made him question everything he knew about psychedelic drug use. "My views are a lot more realistic now, in a sense," he says, while his mother sits beside him, listening. "My first few experiences, after researching psychedelics, the idea of having such a disaster trip never really hit me. I always thought, 'I can handle myself, I'm responsible,' or whatever. I felt like I was always in control." Tom's trip could have been so much worse. In June 2013, for instance, a 17-year-old named Henry Kwan took a drug that was sold to him as LSD. The star student was calmly studying at his desk when his mother and 14-year-old sister left the family home in Killara, in Sydney's north, to go shopping. On their return, they found him acting very strangely and talking nonsense at high speed. After rocking back and forth on the floor in the foetal position, Henry suddenly got up and exclaimed, "I want to fly. I want to fly." He ran outside, where there was a tense stand-off with his mother and sister that brought neighbours to their windows. The teenager then dived head-first from a third-floor balcony and died on impact. While under the influence of LSD for the first time with a friend in July 2015, Arthur Cave – the 15-year-old son of Australian singer and songwriter Nick Cave – died after falling 18 metres from a cliff in England. Hours earlier, the teenager had taken a smiling photograph of himself and shared it with friends on Snapchat. Prior to his third-floor balcony fall, Henry Kwan had taken a synthetic hallucinogen called 25I-NBOMe, which is much stronger than acid. "What we've seen over the last five years is people taking NBOMes at very high doses, without realising what they're taking," says Dr Monica Barratt, who works on the Drug Policy Modelling program at the University of NSW. "At high doses, NBOMes are actually toxic to the body, and we don't see that with LSD. That's one of the reasons why we see the NBOMe series as more dangerous."

Despite the significant difference in potency between the two, Tom has heard that around here, NBOMe compounds are sometimes "sold as acid, but they're not. There's research that two tabs can kill you." "Is that what you took?" Jasmine asks, horrified. "No," he replies. "I tested it." "Okay, good," she says, relieved. According to the 2017 Global Drug Survey, which was conducted in partnership with harm-reduction groups and international media organisations including Fairfax Media, the typical Australian LSD user who responded to the survey was 20 when they first tried the drug, and were at home with friends when they took it. The most common form of the drug was in tabs, for which they paid $19 each. In this survey, which is not a representative sample, more than three-quarters of the 5700 Australian respondents had used illegal drugs, and about one in three had used them in the past month. Only 12 per cent of Australian respondents to the survey had used LSD, which was less commonly used than cocaine (17 per cent) and MDMA (21 per cent), though more common than magic mushrooms (8 per cent). Tom's body bears the marks of his bad trip: the bruises have faded, but he required stitches in six locations on his right side, including his shoulder, hip and glute. "He's quite disfigured, and it's unfortunate that it's on his back," says Jasmine. "He can't see it, but I'm reminded of it whenever I see his dark, purple scars."

The silver lining to this traumatic event is that their relationship has improved. Over a glass of white wine on a Friday afternoon, Jasmine says quietly, "We're closer now because of it. I feel like I've got a much better understanding of his rationale, through the counselling I've done. I see a lot of myself in him: I definitely had the reckless drive in me, but I was probably worse than him in a lot of ways. I've got more respect for the way he tried to research what he's done, and put it into place. I was always much more knee-jerk and opportunistic about that stuff." During quieter moments, Tom has come to realise how much the incident weighs on his parents. Tom's father, Karl, remains incredulous about his son's actions. "I thought I knew him well enough. I wouldn't have ever imagined that he'd do something like that," Karl tells me. "It scares me that despite all the conversations we've had – about the risks and all those things – that he would still think it's okay to go ahead and do what he did. That's the one thing that really rankles me. I think he's learnt the lesson, I really do. Hopefully when turning 18 or 19, that risk assessment changes, and they're just not going to do stupid things like that." He pauses. "But I can relate it to myself. I know I did some dumb things at that age." Jasmine has since received phone calls from other parents seeking advice about hard topics of conversation. "People have come out of the woodwork and called on quite a few occasions now, which is nice," she says. "I just hope I give them the right advice. About drugs, or 'Oh my god, my kid's just been caught!' or whatever. People are reaching out quite a lot, and you feel honoured when somebody does. It's that old 'friend in need' thing." What does she tell them? "Don't freak out, don't panic, and don't go into 'spin mode'," Jasmine replies, while eying off the black cat as it stalks in the garden. "Just go off, talk to professionals, and let everybody know that you're talking to professionals. As a parent, you collect horror stories, and we think that by telling them, it's going to deter the kid. But it's not. If they want to try something, or do something, they're just going to go ahead and do it. You're sort of wasting your breath in a lot of ways." Tom still hasn't hasn't settled on what career direction he'll follow, but he knows he wants to be creative. His bedroom is a tidy refuge of colourful artworks, most of them drawn by his own skilled hand with water-based marker pens. After stepping outside onto the balcony, he looks up to clock a brilliant orange sunset that streaks the fading blue canvas. "Oh, cool sky tonight!" he says, grinning, while currawongs sing in the fading light. "That's neat. We don't get that sky every night."

It's just the two of us here now, while Jasmine is busy in the kitchen preparing to host friends for dinner. Tom strikes me as a smart kid. He's curious about the world and his place in it. His surfboard and drum kit lie downstairs, while his love of art seems to be the consuming passion. He has a part-time job. He has no shortage of interests, and illicit drugs happened to be one of many until that night. "If I hadn't had that experience, I think I definitely would have kept up the same attitudes toward it," he says. "All my other trips had been so fluent; nothing had gone wrong with them." As a result of that wake-up call, and of the counselling he received in the aftermath, the LSD "monster" described by his mother has been led back into its cage, willingly. What happened during that trip scared the shit out of Tom. He's still processing it, and its marks will be branded on his skin for life. "For the next two years at least, I just want to knuckle down and set up a future," he says, arms crossed. "I want to have that as my main focus, really. I can't afford to be doing that kind of stuff." Some of his friends from his previous school are still smoking pot and "a few other things", and they've tried to push Tom into joining them, like he used to do. He's resisted their pressure because he's promised himself he won't take those risks any more. When his friends ask him about experimenting with powerful drugs like LSD – as they inevitably will – what will he tell them? "I think I would start off by saying the negatives towards it, and how bad the worst-case scenario actually is. You could die or seriously kill someone else," Tom says. "It would depend on their approach: if they were asking in a way that indicated they were definitely going to take it, I'd give them my idea of harm reduction, that you've got to have someone there with you, and don't go taking ridiculous doses." Most importantly, he will tell them to be very, very careful about self-experimentation, because they may not be as lucky as he was. * Names have been changed. For national drug support and information, visit livesofsubstance.org/resources-information