The debate over synthetic drugs hit a high this week, with protests on the streets and outside stores.
Parents and former users are calling on the Government to ban the products altogether.
But what exactly are in these drugs, and how were they invented?
A stint in prison was a wakeup call for former K2 addict David Pine, who now wants to see the products banned.
"A lot of people out there will hate me for doing this, but I don't really care; it's for people's safety," says Pine.
The drugs are just as bad for animals. Robyn Higgins' dog, Chief, almost died after eating a packet of K2 he found on their property.
"He was an absolute wreck, and we were a wreck too because we thought we had lost him," she says.
Most of today's products are based on cannabinoids developed 18 years ago in an American University lab. Professor John Huffman was doing cancer research to find synthetic alternatives to medical marijuana.
But this week he told the Otago Daily Times the compounds were "not meant for human consumption. Their effects in humans have not been studied and they could very well have toxic effects. They absolutely should not be used as recreational drugs.''
Synthetic highs begin as a potpourri of dried aromatic plants. Powdered chemicals are then usually mixed together with acetone, which bonds the compounds to the dried leaves.
The Government has tried to fight back, banning 35 substances in the past few years. That's forced more than 50 synthetic products off the shelves.
But it's a cat-and-mouse game with manufacturers. Two more substances were banned this week, but a new legal blend of K2 was on sale within 24 hours.
A proposed bill is being debated, which would reverse the burden of proof, forcing any new products to go through clinical testing similar to new medicines.
"All of the costs will be borne by the applicant, and that could be up to $2 million a product," says Associate Minister of Health Peter Dunne.
Mr Dunne says the issue will be dealt with urgently.
"I'm trying to have that fast-tracked as quickly as possible," says Mr Dunne. "The bill will only be at the select committee for a couple of months instead of the usual six months."
He expects the bill to be passed in July, taking high-risk drugs off the market by August.