A group that tests drugs at festivals across the country say they have seen more high-potency ecstasy pills this season than ever before.
A typical dose of ecstasy, which is also commonly known as MDMA, ranges between 80 and 160 milligrams.
However, so far this festival season KnowYourStuffNZ has tested some pills weighing up to 340mg, and one weighing 580mg.
The group's director, Wendy Allison, said their tests indicated the large pills were mostly MDMA.
"This suggests that we're looking at pills that may contain up to two to three standard doses rather than a single dose," Allison said.
"And the thing we are concerned about there is people tend to think of one pill as one dose."
Allison said the explosion of high-level drugs had been happening throughout the United Kingdom and the rest of Europe.
"Trends over there tend to make it to New Zealand eventually, so we've been kind of expecting it, but this is the first year that we've had any real confirmation of it happening."
There have been reports in the United Kingdom of a string of deaths related to high-potency pills and MDMA poisoning.
While there was a danger to all festival-goers who were buying pills through the black market, Allison said most Kiwis made informed decisions when given the chance.
"What we have found is that when people find out that their drugs aren't what they were supposed to be, more than half will turn around and decide not to take them.
"What I take from that is that drug users will make the decision to stay safe if they are given the opportunity and the information to do so."
Allison also stated that anecdotally it was younger people who were making sensible decisions.
"They're a lot more willing to let go of an experience now to have one later."
The group issued a warning about three particular pills they fear could have potentially high doses: green guccis, a green pill stamped with a Gucci logo; yellow rolexes, which are shaped in the form of a Rolex crown, and pink porsches, which are shaped like a Porsche logo.
Allison also had some words of advice for anyone who had been sold drugs at festivals across the country.
"If they are taking a pill of an unknown quantity, that they take a fraction at a time and then wait."