The mother of a Cork teenager who died after taking a combination of a psychoactive drug and ecstasy tablets has warned others not to take synthetic drugs.

Joan Deasy made her plea as she left the inquest into the death of her 16-year-old son, Michael Connacchia, who was found unresponsive in their home in Deerpark in Cork city on 16 January 2017.

A verdict of misadventure was returned by the Cork City Coroner.

Speaking as she left the court, Ms Deasy pleaded with young people to "never take any synthetic drugs".

Michael's father, Roberto Cornacchia, said young people have to be really careful with what is out there.

"They should play sport, and live, that's what I did at their age" and forget all about drugs, he added.

His friend told the court that they had arranged to buy an eighth of an ounce, or €200 worth, of cocaine from an unnamed person via Facebook Messenger on the night of 15 January.

He said that Michael used a door key to snort some of the cocaine on their way home.

At one stage, close to Neptune Stadium, they found they could not walk for about five minutes such was the effect of the drug.

He said they went back to Michael's home, where they smoked some cannabis. He remembered feeling dizzy, sweating and struggling to keep awake.

He had taken cocaine before but this was nothing like that. The next thing he remembered was being woken up by Michael's mother, who was crying.

Ms Deasy said she never knew her son was taking drugs. Like other parents she checked his pockets but never found anything.

She said that he had learning difficulties as a young child and had been well supported in national school but struggled in secondary school. A talented footballer, he loved his music, being on Facebook and playing with his Xbox.

She found him in an upright position on the sofa and said she knew by looking at him that he was dead.

Investigating Detective Garda Darragh Murray told the court that the two teenagers believed they were buying cocaine. However, when gardaí had it analysed it was found to be the psychoactive drug U-47700 or U4.

Garda Murray said there the HSE put out a national alert about the drug at the time. There have been no further seizures of the drug since.

He told the court that it commonly comes in from Asia via post to a random address. In this case, it was never identified where it came from.

Assistant State Pathologist Dr Margaret Bolster said the opioid was developed in the 1970s but proved to be very addictive and was abandoned. The level in the youngster's body was higher than in 11 other recorded fatalities.

She agreed with Coroner Philip Comyn when he said taking these drugs was like a form of Russian Roulette - that people do not know what they are getting.

Returning a verdict of misadventure, Mr Comyn said he is seeing more and more of these cases. He said there was little consolation he could offer the family other than that their son had not suffered as he would have slipped into a deep coma.

But, he said if any good was to come from today, it is that young people should realise the dangers of buying illicit drugs.

Mr Comyn reminded the court of the death of another youngster 18-year-old Alex Ryan, who died after taking a synthetic hallucinogenic drug, N-bomb.

He said following Mr Ryan's death, he wrote to the Department of Education and to the representative bodies for secondary school principals and teachers, urging them to hold awareness classes for students in 4th year.

He said the only one who got back to him was the Department of Education. He would be writing again.

In January, a 17-year-old boy pleaded guilty in connection with the death of the teenager. He was given a 12-month detention and supervision order.

Judge Gerard O'Brien had adjourned sentencing last November after he expressed concern about the teenager's lack of insight into his drug dealing.