Banning synthetic cannabis has proved ineffective and has forced the sale of the products underground, a local business owner says.
While police say they are seeing improved behaviour, particularly from those in the CBD, a Rotorua Hospital spokeswoman says there is evidence synthetic cannabis is still being used.
Last month it became illegal to sell, supply or possess psychoactive substances, including synthetic cannabis, under the Psychoactive Substances Amendment Bill, which was passed under urgency in Parliament.
The move was sparked by public protests and concerns about the safety of such substances. David Young, the owner of Skin Graft, which used to sell the products, said the law change had not solved anything and he had heard it was now being sold underground.
"I think it wasn't a good move. From what I've heard on the news and other platforms, it's just forced it underground," he said.
"But that was expected, people knew this would happen when talks first began about banning synthetics."
Mr Young said the law change had left his business $60,000 out of pocket.
Before it came into effect, he sent the stock he had, all 8000 packets of it, back to the manufacturers.
Mr Young said while most manufacturers had got in touch and settled debts, two companies disappeared off the radar owing him about $60,000.
Rotorua police alcohol harm reduction supervisor Sergeant Mike Membery said he was not aware of any arrests for possession or sale of synthetic drugs.
Since the ban, police had noticed a positive difference in people's behaviour, particularly in the CBD, he said.
"It's certainly improved. I mean it can still improve further, but the people who were on synthetic highs are certainly a lot better to deal with."
Lakes District Health Board communications officer Sue Wilkie said Rotorua Hospital's emergency department saw a spike in presentations in the seven to 10 days after the law change, but the numbers had since fallen.
There was evidence that the drugs were still being used, she said.
"Our ED has seen a few patients who are still using synthetic drugs in recent weeks," she said.
Ms Wilkie said that since staff were used to dealing with a range of patients, the law change had had little, if any, effect on the running of the emergency department.