Health Minister Tony Ryall is warning people not to try to stockpile synthetic drug products before they're pulled off the shelves, Radio New Zealand reports.
Parliament on Tuesday night passed legislation under urgency effectively banning all synthetic cannabis and party pills.
The legislation will come into effect from midnight Wednesday. It will then be an offence to sell, supply or possess synthetic drugs, and possession of even a small amount will attract a $500 fine.
The minister, Tony Ryall, said police would be actively enforcing the new laws. "It will also become illegal to possess these products so anyone thinking of stocking up today should bear that in mind," he said.
Wayne McFadyen, whose son uses legal highs told Radio New Zealand's Morning Report programme the drugs have turned his son into a sick, angry and threatening young man.
He believed the ban would not work because the industry would find ways to bring new drugs onto the market.
"They'll change the chemicals or whatever, and we're still going to have the same problem, or the black market. But it's a bit little too late because the Government should have acted on this 12 months ago.