An explosion in the number of shops selling legal party pills has Christchurch City Council calling in its lawyers to see what can be done to control their spread.
The council has labelled them a scourge on the city and is considering by-laws as a way to deal with the boom.
Cosmic Corner owner Mark Carswell estimates there may be as many as a thousand other outlets selling herbal pills and nitrous oxide around the country.
Along with the pill, nitrous oxide, which is commonly used in the catering industry for whipping cream, is now being retailed for its euphoric properties.
"I think throughout New Zealand there's probably hundreds, if not over a thousand retailers of the legal highs," Carswell says.
A store selling 'herbal' highs and nitrous oxide near a school in the Christchurch suburb of Hornby has already attracted community protest.
Broughton says the council particularly wants to control the sale of party pills based on BZP or benzylpiperazine.
"BZP is actually very dangerous and very harmful and has actually been banned in the [United] States."
According to one source, an estimated 50,000 packets of party pills are sold every month and Peter Shaw says they could be "gateways" to harder illegal highs.
"While they got their initial thrills from the supposedly safe legal stuff, it wasn't enough and they had to go on."
And Shaw says the goods are proving popular with all age groups.
"It's not just as some people imagine young people, but older people - my age - that are queuing up as well. Unfortunately there seems to be a trend that people are seeing [nitrous] as their nightcap after a night on the town."
While local authorities are proposing controls on the sales of herbal highs, parliament is considering a law change to make them R18.
The age restriction is a move that Cosmic Corner's Carswell would support.
"It's the same as alcohol and cigarettes, it's an adult product,
as simple as that."
The Christchurch City Council will have a report back on their own legal options in a month.