"But this doesn't mean we've seen a reduction in the use of synthetics. We're still getting problems with them and they're still serious, we would be kidding ourselves to say things are great now.
"Where we seem to be at the moment in this whole process is the people who manufacture this stuff are going away and having stuff tested for safety before putting it on the market so there's a bit of a gap between now and the next phase."
Mr Gilmour said to expect a new wave of products in a few months to a year.
"First they were marketed as social tonics, then legal highs so it will be interesting to see what route they take next.
Tauranga Hospital Emergency Department clinical lead Derek Sage said patients were not categorised by use of legal highs but in his experience there appeared to have been a drop in people suffering the effects of these substances since the law change.
"Just before the law change came into effect there was a peak in usage and presentations, as if people were rushing to use them before they became illegal," Dr Sage said.
"Since then people have been less forthcoming about what they have taken and we do not formally test for these substances unless it would alter our treatment of the patient.
"The main issue we have to deal with relates to patients for whom the substances trigger a psychotic episode. Those patients can then become extremely difficult to manage and treat."
Mike Lawrence, proprietor of Special T Discounter (formally Puff n' Stuff), said sales had plateaued as people regulated their use of synthetic products.
"People have been there and tried that. It's regulated itself. People are making their own minds up about that stuff. It's very positive as far as the law change has gone.
"Our store has been approved and been told by officials we can give advice to people whether they're first-time users or people who are using a bit too much."