By Sallie George
For just £5, he was promised a "mellow hit, similar to acid but more enjoyable".
The teenager has suffered severe flashbacks
But for 18-year-old Justin Stevens (not his real name), the decision to experiment with a little-known drug called Bromo Dragonfly very nearly cost him his life.
His lung collapsed, his heart stopped twice, and his mother was told that in the unlikely event her son survived, he could be left with permanent brain damage.
Just days after leaving hospital, Justin spoke to BBC News online about why he will never take drugs again - and why he wants his experience to serve as a warning to other young people.
'Swarm of bees'
Heading into Guildford, Surrey to meet a dealer, Justin and his friends had planned a night experimenting with drugs.
"We knew a guy who had some stuff, he had lots of different things, research chemicals, ketamine, cannabis - we just wanted to experiment," he said.
"I'd not tried anything that intense before - I'd smoked a few spliffs but never really gone further."
The group's choice, Bromo Dragonfly, a Class A hallucinogenic, was in liquid form and came in a brown vial with a pipette.
Four drops were put onto each boys' hand, which they then licked off. It cost them £5 each.
About two hours later, the teenagers began to feel the hallucinogenic effects of the drug.
Three hours in, Justin's condition became dramatically worse.
He said: "I started getting really hot, and slightly panicky, and couldn't concentrate on anything.
The teenagers planned a night of experimenting with the drug
"My friends said I started sweating profusely so they took me outside to get some air.
"I didn't have any shoes on, as they couldn't get me to put them on. Then when I was outside, I started to rip my clothes off."
The teenager became convinced he was surrounded by a swarm of bees, and began swatting at the air.
As he did, he fell into brambles and nettles, but continued to fight.
"It took a while for my friends to restrain me.
"I've got scars all over my arms, my stomach and my face from the brambles, some of them are really quite deep."
As his friends tried to help, Justin started convulsing, and then stopped breathing, before having another fit.
"I threw up and then inhaled the contents of my stomach, and my lung collapsed," he said.
"As the ambulance arrived I had another fit and my heart stopped.
"They brought me back in the ambulance, and then my heart failed again as we reached the hospital."
His mother Kathryn rushed to her son at Frimley Park Hospital, only to be told by doctors that his chances of survival were slim.
But just days later, he returned home, having made what doctors told him was a "miracle" recovery.
His mother said: "My initial reaction when they said he could come out of hospital was just to go into panic - how do I make sure this doesn't happen again? I thought I wouldn't be able to sleep at night.
"But this has changed him completely - he will never do this again, and he is very keen to make sure other people don't go through it."
Since leaving hospital, Justin has suffered severe flashbacks, and had concerns about the long-term effects of the drug.
Martin Barnes, chief executive of DrugScope, said Bromo Dragonfly was one of a number of hallucinogenics where the effects could be similar to LSD, but little was known about it.
He said: "The drug is a liquid and taken in similar ways to LSD - usually swallowed on sugar lumps or on blotting paper - but as it is relatively rare, little is known about its effects or what may or may not be a 'safe' dose.
"Given uncertainties about potency, dosage and the drug's unpredictable effects people should steer well clear if they are offered the drug."