"The shopkeeper and we were gently trying to revive the guy and he just rolled into the street and started spasm-ing around.
"He would get to his feet, then start spasm-ing.
"He didn't know what was going on and would just collapse again and rolled further and further on to the road into Customs St.
"We all went out and stood kind of around him so that the traffic knew to go around."
After about five minutes, he got to his feet and started walking down the street and the group followed.
By that time St John Ambulance had arrived and took over from them.
Genter said the shopkeeper knew his name and had said "he was quite a good fella", that he usually used P but that he was on synthetic cannabis.
"He lives on the street and hangs around that shop so the shopkeeper knows him and said he was one of the more gentle of the people living rough around that area and that he wouldn't hurt anyone."
He had had mental health issues as well as addiction. She guessed he would be aged in his 30s or 40s.
Genter said the ambulance took about 10 minutes to get there and that she was pleasantly surprised.
She said the crisis needed urgent action from the Government.
"Homeless people are particularly vulnerable because they are looking for anything that will help them sleep and get through these very cold difficult nights."
The police should be looking for the source of the product that was killing people "but it is going to be difficult to get to the bottom of it if we aren't taking a health approach to the people who are falling victim and using it".
"It makes it harder to seek help when we treat drug use as a criminal issue rather than a health issue."
The Government needed to be reaching out to the people who had been affected to get to source and to ensure there was testing available for users.
But there was a gap right now, she said.
"You either go through the police or you take a health approach and there really isn't anyone in between."
The police needed to be resourced with addiction and health specialists to work with them to curb the ongoing epidemic.
Genter also said that if cannabis were legalised, the problems would not be so severe.
"I think if cannabis were legal we would have less of a problem with these dangerous alternatives."
Prime Minister Bill English told reporters in Auckland that anyone buying synthetic cannabis products needed to be aware they were potentially lethal.
"We're not sure there are seven deaths - there could be more - so anyone that is in that part of the community that is using these products needs to be really careful.
"The products they are handing out to others could be lethal because no one knows what's in them."
In the first instance, he expected the police to deal with any potential offences that had been committed in the use and distribution of an illegal substance.