Police in Dunedin had a ''pretty rough weekend'' dealing with people complaining of withdrawal from psychoactive substances.
Interim approvals for all psychoactive substances were revoked at 12.01am on Thursday, effectively making the use, sale and manufacture of the products illegal.
Four people complaining of withdrawal symptoms were arrested by police yesterday afternoon for behavioural offences, Southern District Command Centre deployment co-ordinator Senior Sergeant Matt Scoles said.
Those charges included threatening to kill, and possession of an offensive weapon.
National Poisons Centre toxicologist Dr Leo Schep said the centre had received as many calls from people suffering from withdrawal effects in the first 11 days of May as it did for the month of April.
Snr Sgt Scoles said several people police dealt with had ''made the comment that they aren't coping very well with withdrawals''.
''It creates a bit of a safety issue for police and members of the public.''
They were behaving differently from how they normally would, he said.
A Dunedin Hospital spokeswoman said the hospital dealt with several people who were users of psychoactive substances.
''We have had presentations over the weekend, but whether they are from withdrawals or from symptoms of the drugs is a bit unknown at this stage,'' she said.
It was ''too early to tell'' if there had been a spike in presentations.
Snr Sgt Scoles said while none of those dealt with during the weekend were violent, there was concern for their state of mind.
''The concern is based around the unpredictability and irrationality of these people.''
Several others had come to police attention because of the symptoms of withdrawal and were ''complaining of issues with their stomachs and toileting'', he said.
Dr Schep said eight people had contacted the Dunedin-based centre so far this month because of withdrawal symptoms, while last month seven people contacted the centre.
While the ban would put support services under pressure, they were prepared for the increase in demand and well suited to meet it, he said.
Police had no issues in regards to illegal retailing of psychoactive substances, Snr Sgt Coles said.
Where to get help
• The Alcohol Drug Helpline: 0800 787-797.
• The Addictions Treatment Directory: www.adanz.org.nz
• Home-treatment-based Detox Service: 476-6063.
