A coroner has ruled that using synthetic drugs led to the deaths of two men - and is investigating whether the deadly substance played a part in up to 50 other fatal incidents.
Findings were released today into the deaths of Taupo man Isaiah Terry McLaughlin and Shannon James Thomas Coleman-Fallen from Rotorua.
Both deaths were directly linked to synthetic drugs.
There are currently about 50 deaths nationally which the coroner's officer says "provisionally appear to be attributable to synthetic cannabis toxicity".
Coroner Michael Robb conducted inquiries into the deaths of McLaughlin and Coleman-Fallen and released his findings publicly this morning.
Coleman-Fallen died on 17 September in a van parked at the boarding house where he was living.
Coroner Robb said the 29-year-old labourer was invited by another resident to go for a cruise.
They left the boarding house in a van and soon after, discussed buying synthetic drugs.
"Having purchased synthetic drugs, they drove the van to a park where they drank alcohol and consumed the drugs," said Coroner Robb.
The pair used a bong to smoke the drugs and then were "unable to keep awake".
When the other resident woke later, he saw Coleman-Fallen lying face down in the back of the van.
"He spoke to Shannon and received a groan by way of response," the findings stated.
The other resident, whose name was suppressed by the coroner, drove the van back to the house and told Coleman-Fallen he was going inside to sleep.
Coleman-Fallen groaned again.
The resident later told police that he did not want to try and wake up Coleman-Fallen in case he was "angry" at being roused from a "synthetic nap".
"The following morning [the other resident] went out to the van and found Shannon still in the back of the van and in the same physical position, lying on his front on building items.
"[He] gave Shannon a whack on the thigh and in doing so realised Shannon's body was rigid. [He] got into the van, stood over Shannon and lifted him up by his clothing.
"He saw Shannon's face was blue, with vomit and blood.
"It was clear to [him] that Shannon had died sometime overnight," said Coroner Robb.
A post-mortem examination revealed Coleman-Fallen had consumed alcohol, methamphetamine and two types of synthetic drugs.
"It appears his drug consumption led him to be so incapacitated that when he vomited this resulted in him asphyxiating," said Coroner Robb.
"I conclude that consumption of drugs left Shannon effectively in a comatose position from shortly after their consumption and Shannon lying or collapsing face down in the back of the van.
"The cause of his inability to move when he vomited and, as a result, the cause of his asphyxiation was the consumption of drugs."