UPDATE: Another eight people were rushed to hospital after reportedly overdosing on a hallucinogenic "zombie" drug on the Gold Coast.
It follows another eight people who were hospitalised in the early hours of Saturday morning, believed to have taken the same drug.
The mix of young men and women, aged between 18 and 25, were treated by paramedics at licensed venues across Surfers Paradise and at a residence at Labrador.
Paramedics and police say the patients all suffered severe hallucinogenic reactions and began behaving erratically and aggressively.
Queensland Ambulance Service inspector Stephen Burns said it was the biggest outbreak he'd seen in his 24 years on the Gold Coast.
Of the eight reported on Saturday, patients suffered severe reactions and began behaving erratically. Two of the men were in a serious condition, another put into an induced coma.
Police also had to protect paramedics as one intoxicated man was hallucinating.
The so-called "zombie" drug is thought to be "Flakka" -- a synthetic hallucinogen which has a notorious reputation in the United States where it is also dubbed "gravel".
It combines the stimulation from methamphetamine with the hallucinogenic properties of LSD.
Its scientific name is Alpha-Pyrrolidinopentiophenone or Alpha PVP.
Police have told News Corp they now fear the drug could claim more victims at next weekend's Gold Coast 600 motor race, and at Schoolies later in the year.
Gold Coast police district duty officer Senior Sergeant Bruce Pearce told the Sunday Mail the users were showing "extreme behaviour".
"I'm sure it was a very scary situation for those people.
"We just want to get the message out there that these are dangerous drugs. You don't know what's in them ... so don't take them."
Update your news preferences and get the latest news delivered to your inbox.