Young people are being warned about the dangers of taking party pills after an alarming increase in the supply of "dodgy drugs".
University orientations are among the events targeted this year with 65 percent of MDMA samples brought in by Otago students actually containing a dangerous psychoactive substance.
Drug testing clinics have moved out of the shadows and into the open after being legalised by the Government.
That's seen a huge increase in demand for these services revealing many samples aren't what people think.
"If you're going to take drugs and you haven't had them tested, you're flipping a coin as to whether you'll have a good time or end up in hospital," Know Your Stuff Managing Director Wendy Allison said.
Testing by the Know Your Stuff team during Otago University's O-Week found almost half of all drug samples brought in by students were actually psychoactive substances called cathinones, sometimes marketed as 'bath salts'.
That included 65 percent of all MDMA samples containing the dangerous stimulant, eutylone.
"If people take too much of it, they are having significant health issues to do with stimulant overdose," Allison told Newshub.
"So we're talking about heart palpitations, seizures, hallucinations, psychosis, that sort of thing in high doses."
It's a worrying trend. A year ago just 2 percent of all pills and powders tested contained these substances.
The Otago University Student Association (OUSA) believes making these services available is the best way to protect young people.
And hopefully, that information passes back through their peer groups as well to say, 'hey guys maybe think twice before you take things'," OUSA CEO Debbie Downs said.
Figures from music festivals and Canterbury's orientation events aren't much better.
At the Electric Avenue event over the weekend, 24 concert goers required hospital treatment after taking drugs, including two in a serious condition.
There is one positive from the summer results - around three-quarters of young people said they wouldn't take a substance after finding out it was something much riskier.