The parents of a teenager who died after taking a substance at a music festival this month have urged parents to talk to their children about drugs, saying it is a problem that affects everyone regardless of class.

Jack Downey, from Clonmel in Co Tipperary, was at the Indiependence music festival in Mitchelstown, Co Cork, over the August bank holiday weekend.

The 19-year-old is believed to have ingested a substance and he complained of feeling unwell at the festival medical centre.

He was treated there before being transferred to Cork University Hospital, where his condition deteriorated.

Speaking on RTÉ's Marian Finucane show with Brendan O'Connor, Jack's parents Johnny and Elaine Downey said they never thought this could happen to them.

"These are young smart, educated people who think they're invincible. There's no class to it. We're afraid to ask the questions of our own, because we're in a bubble and we think it's not going to happen to our own," said Johnny. "We need to cop on."

Elaine said: "I never thought this would happen to me. I never thought my fine son would be in the cemetery. We're all heartbroken, there's no way back for us, but there might be for someone else."

Jack, an only child, was passionate about the GAA, and wanted to become an accountant since he was eight years old. He was studying in Cork.

He was "six foot two and strong man,'' said his father. "He had a presence, he'd walk into a room and he wouldn't have to say anything, he'd just smile and he would take over".

On the Friday night of the August bank holiday weekend, the parents got the call from a colleague of Johnny, who is a garda in Tipperary.

They were advised to get to Cork University Hospital immediately. "Initially I met two colleagues who are now stationed in Cork but who had been in Tipperary one time. Jack being an only child would have been around the garda station a lot, so everybody knew him."

The doctor in CUH told them that "Jack is seriously seriously ill and his life is in danger".

The parents complimented the staff in the hospital. Elaine said: "We can't thank them enough, their kindness to Jack, their kindness to us."

They also said they got some comfort from the way that the news first reached them. They were grateful to the friends, hospital staff and the gardaí who supported them.

"Our understanding was that he was at the festival and he took this substance, we'll eventually find out what it is and what concoction it was," said Johnny.

The parents said they felt "duty bound" to make the unusual move to open up the room in ICU to a large number of friends and family.

Lots of Jack's friends came to see him, and Johnny and Elaine said they wanted the young people to see the dangers.

It was "one mistake,'' said Johnny.

"To see Jack there, lying in a bed, tubes coming out of everywhere," said Elaine. "There, our lovely boy, ravaged."

Johnny said "Jack was well versed on the dangers. I would never have suspected it was going to be our Jack. It affects everybody, the cards and letters we've got, we've only opened a fraction of them.'

"There's no quality control in this. You often hear the words 'bad batch'.

"We need to talk, that's the bottom line."

Remembering Jack, they said he used to repair hurleys and was very close to his grandfather, Stephen, whom he would talk to on the phone every evening.

He and his mother travelled regularly to club matches. "He was a great supporter of all the different clubs. He just enjoyed meeting people and getting sliotars from matches," she said.

Johnny said: "It's hard to get out of bed some of the days. You've got to get up, you've got to face the world. I have found it hard. You put one foot forward. I realised after Jack's death that friends and family are very important."

He praised the "phenomenal support" from everybody in their lives - family, friends, the Garda Síochána family and the local GAA clubs.