A nation-wide study of our wastewater and online search data has revealed the worrying trend is booming.
The phrase 'kitty flipping' might conjour up playful furballs or racy sex acts, depending on your turn of mind, but the reality is far more perilous.
The term refers to combining the party drugs ketamine and MDMA (ecstasy) - and new research shows it's on the rise in Australia.
A new Australia-wide study of our wastewater has revealed that ketamine use has more than doubled in just four-and-a-half years.
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So exactly what is 'kitty flipping', why are more people doing it? And just what exactly is so dangerous about it?
The rise of ketamine as a party drug
Independently of ecstasy, the use of ketamine as a party drug has risen steeply in Australia in recent years, mirroring its growing popularity in the US, including amongst Hollywood celebrities.
It's a trend that drew headlines with former 'Friends' actor Matthew Perry's ketamine overdose in October 2023, which led authorities to uncover a widespread network of illegal trade catering to Hollywood's elite.
Ketamine is a pharmaceutical drug used as an anaesthetic which has become popular to treat severe pain and depression, due to its dissociative effects.
When used correctly in a hospital setting, it's considered very safe and effective.
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In 2020, detections of ketamine in Australia's wastewater were largely consistent with those kinds of prescribed uses, according to today's research by a team from Adelaide University.
But that soon changed.
"Patterns started emerging of substantially elevated excretion on weekends, suggesting an increase in recreational, or non-medical use of the substance," explained Professor Cobus Gerber from the university's School of Pharmacy and Biomedical Sciences.
Gerber and his team have studied the wastewater of Australia's major cities and regional centres in every state and territory from 2020 through to 2025.
In December 2020, ketamine use averaged 2.7mg per day for every 1000 people but by April 2025, that had risen to 5.8mg per day - more than double.
The largest doses were found in affluent areas and inner city locations.
But why are people mixing it with MDMA?
Combining ketamine with other drugs isn't new.
"The drug is often consumed alongside other illicit substances to heighten feelings of euphoria and dissociation," explained Gerber.
'Pink cocaine', the concoction found in One Direction star Liam Payne's system following his fatal balcony fall in 2024, is actually most commonly a mix of ketamine and other drugs such as methamphetamine and caffeine.
However, online search data in Australia shows a recent rise in searches for the term 'kitty flipping'.
This specifically refers to combining ketamine with MDMA, ususually by taking MDMA first and then snorting or ingesting ketamine although sometimes combined pills or drinks are used.
Why is 'kitty flipping' so dangerous?
Any unprescribed use of ketamine comes with risks, but the typical harm reduction strategies for using single drugs (start low, stay hydrated, test your drugs) cannot account for the way the drugs interact.
For example, MDMA raises body temperature and heart rate, while ketamine impairs the body's ability to regulate its temperature.
When combined, this can result in an extremely high and unstable body temperature.
The combination of the two illicit drugs can also cause a potentially deadly build up of serotinon in the body, as well as place enormous strain on the heart.
To make things worse, MDMA slows digestion, so the high can hit later or harder than expected.
In the US, the popularity of 'kitty flipping' has already been associated with a significant rise in ketamine-related drug overdoses.
In Miami alone, 68 people died from an overdose with ketamine in their system in 2023. Prior to 2017, that number was fewer than 10.
Experts are now urging more research be done in Australia to track down where these drugs are originating from.
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