Leon Danks, aged 18, of Richmond Park Rise, Sheffield, died on January 22 this year after being found unresponsive in bed at his family home.
The court heard that Leon had a history of mental health problems and had tried to take his own life on at least one occasion.
He was referred to the Child and Adolescent Mental Health Service - CAMHS - in November 2018 by his GP Dr Ruth Simpkin, but due to the current 18-week waiting time was never able to get the help he needed.
An inquest into Leon’s death at Sheffield Coroners’ Court on Thursday concluded that he died as a result of misadventure.
Earlier the court heard from a pathologist and the doctors and social workers who saw Leon in the months and years before his death.
Consultant pathologist Professor Kim Survana said that toxicology reports showed that he had taken two drugs not normally screened for in post-mortem examinations.
An overdose of the ‘new psychoactive substances’ - one a synthetic opioid drug like Fentanyl and the other a pseudo cannabis type drug - were ‘the most reasonable cause of Leon’s death’, said Dr Survana.
“You cannot predict how these drugs will work and I regard them as dangerous,” he said.
Leon - who was a trainee mechanic - had attended the emergency department at Northern General Hospital on three occasions in the year before he died.
On the first occasion in March 2018 he had been drinking alcohol and prescription drugs, and had taken THC tablets, a type of synthetic cannabis.
The second time in June he had again taken medication and alcohol while on the third occasion in August Leon had ingested cleaning products and paracetamol.
During his final visit to A&E, Leon was seen by a mental health social worker, David Roberts.
Despite Leon’s insistence he was suffering from schizophrenia, Mr Roberts said they didn’t see any evidence of acute mental illness at that time.
Leon did, however, say he was using drugs he had bought on the internet to ‘self-medicate’ his mental health conditions.
Mr Roberts said: “He was calm, rational and reasonable. We didn’t think he was experiencing a psychotic episode. We thought it may be linked to his substance use.
“He felt he knew better than any psychiatrist because he had done his research and knew what he was taking.”
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