Of those surveyed, only Victoria St News Agency did not stock the drugs.
Health authorities, youth workers and police have seen a spike in incidents related to the legal highs, including use by a 9-year-old, and a 14-year-old who had a heart attack after smoking the drugs.
One Dunedin father has spoken of the heartbreak of seeing his 24-year-old son admitted to hospital after a psychotic episode after giving the drugs up "cold turkey".
Yesterday Associate Health Minister Peter Dunne said testing was being carried out to urgently determine the makeup of products being sold.
New chemical substances would be added to the 33 already banned, but there was a possibility products were illegal. Stockists could face criminal charges if that was so, he said. A version of K2 had already been banned.
Toxicologist Leo Schep, of the National Poisons Centre, spent last week talking to schoolchildren about the dangers of the drugs, and said community concern was at a high point. Dr Schep said the health effects of the chemicals were particularly damaging for young people, given their brains were still developing.
They included paranoia, psychotic episodes and renal failure.
This month a Timaru youth worker went public over her concerns about primary school children using the drugs, citing the case of a 14-year-old who had a heart attack.
Dr Schep, who knew of that case, said the teenager was using the drugs again. The youngest user he knew of was 9.
Yesterday Mr Dunne said the Government banned new products as soon as was possible.
"We have taken out 51 different products ... the difficulty is ... the speed of change is such that we are always playing catch-up."
He said that problem would be solved when, by August at the latest, a world-first regime would make manufacturers prove the safety of products before they could be sold.
In the meantime, there has been an upsurge in community anger and concern about the drugs.
This week Dunedin father Wayne McFadyen spoke out to warn people off the drugs.
Mr McFadyen, who weighs 148kg, said he was tossed around his house "like paper" by his 70kg son trying to withdraw cold turkey from K2.
The 24-year-old is now in Wakari Hospital, sedated and in isolation, after a psychotic episode this week. He had given up a two-packet-a-day habit after seeing the effects on friends.
"His thinking and behaviour just went haywire. He couldn't control himself and ran around our house at 100 miles per hour, would jump up, and be crying, 'Help me, dad, help me, dad.' That was pretty heartbreaking." He said his son also felt suicidal, could not eat or sleep, attacked a neighbour, and repeatedly headbutted a garage.
"I know people who smoke dope who don't do this sort of thing. Maybe they should legalise marijuana and get rid of this other crap."
Synthetic cannabis
• Products first pulled from shelves in August 2011.
• So far 51 different products removed.
• Permanent solution expected by August.
- additional reporting: Otago Daily Times
