A coroner says the death of a man after inhaling synthetic cannabis shows the need for immediate medical help to be sought if someone collapses after using the drug.
Gordon Matenga's findings into the death of Andrew McAllister, who died in Waikato Hospital in August last year after smoking synthetic cannabis and drinking methylated spirits, have been released.
The 49-year-old was socialising with friends and collapsed after smoking synthetic cannabis.
Coroner Matenga said Mr McAllister would often drink methylated spirits and smoke synthetic cannabis to the point of losing consciousness and his friends did not initially take too much notice of his final collapse.
One of his friends told Coroner Matenga he moved furniture away from where Mr McAllister was lying and thought he would give him 20 minutes to recover, but after a few minutes they looked at him more closely and noticed his complexion becoming grey-looking and cold.
"[Mr McAllister's friend] checked for breathing and a pulse. There were no signs of life," the coroner said.
"CPR was commenced and emergency services were called. CPR was continued until paramedics arrived and took over."
Mr McAllister was initially taken to Taupō Hospital, but was later flown to Waikato Hospital.
He developed seizures and testing showed a severe brain injury with no chance of a meaningful neurological recovery.
A post-mortem showed his cause of death was probably a complication of using synthetic cannabis and alcohol.
Dr Paul Quigley, a specialist in synthetic cannabis, explained to the coroner that the drug was produced by placing an active chemical onto dried plant material either in a spray or by evaporation.
"Using the spray method can create issues with consistency of potency as different doses can be created dependent on how fast the chemical is applied onto the plant material," Dr Quigley said.
"A slight pause in one place as the spray nozzle is moved across the plant material, could create areas of greater potency."
Dr Quigley told the coroner the most likely cause of Mr McAllister's collapse was a cardiac arrest, which decreased blood flow to his brain leading to his death.
"Cardiac irritability and cardiac arrest from [synthetic cannabis] has been documented in the literature, including advanced cardiac disease in ... users," he said.
"It appears that [synthetic cannabis] use has the ability to accelerate heart disease resulting in heart attacks (myocardial infactions) in a younger age group (30-40) than expected."
Coroner Matenga has found that Andrew McAllister collapsed as a result of consuming the synthetic cannabis products, AMB-FUBINACA and 5F-ADB.
He has also reiterated Dr Quigley's advice that attempts should immediately be made to rouse anyone who collapses after using synthetic cannabis.
"If the person rouses, [they] should then be placed in the recovery position, and a call for help should be made.
"If the person does not rouse, then call for help and commence chest compressions... Do not delay."
Coroner Matenga ruled Andrew McAllister's death accidental.