What is ketamine and why is it causing concerns in Europe?

Health authorities say ketamine use is up across Europe and recently hit the headlines due to the death of Friends star Matthew Perry.

Ketamine is making waves across Europe, decades after it emerged as a medical anaesthetic in the 1960s and became popular as a recreational drug in the 1980s and 1990s.
In more recent years, researchers have been exploring its potential to treat depression in low doses, and ketamine-assisted therapy clinics have cropped up across Europe, including in the Czech Republic, Poland, Spain, the United Kingdom, and Switzerland. 
But the drug catapulted into the public consciousness after American actor Matthew Perry died from the “acute effects of ketamine” in 2023.
Perry acquired the drug illegally in the United States after first getting it through a legitimate prescription to treat depression and anxiety – underscoring the at-times blurred lines between medical use and dependency.
So what exactly is ketamine, who’s using it, and what is its legal status?
Ketamine is a psychedelic, but it is not the same as classical psychedelics like psilocybin (“magic mushrooms”) or LSD, which can affect people’s perceptions, mood, thinking, and sensory experiences.
Instead, ketamine is considered an “atypical psychedelic”. While it has a dissociative effect and can also alter people’s state of consciousness, their actual experiences may be different than with the classical drugs and vary from person to person.
The European Union’s drug regulator approved esketamine, which uses ketamine as a parent compound, as a medicine for treatment-resistant depression in 2019. It is also still used as a painkiller and sedative in some hospitals and in veterinary medicine.
But because of the dangers of recreational use, ketamine is also considered a controlled substance in several countries, such as Lithuania and France.
Public health scientists use data from wastewater samples to estimate the level of drug use in a community. In 2022, they found generally low levels of ketamine residue across 15 European cities, with the highest levels in Denmark, Spain, Italy, and Portugal.
Even so, the number of illegal ketamine seizures across the EU has nearly quintupled in recent years, from 701 in 2015 to 3,462 in 2022. That represents 9 per cent of all new psychoactive substances seized that year.
Denmark and the Netherlands accounted for two-thirds of the ketamine seized by the authorities in 2022, according to the EU’s drug agency.**
The ketamine in Europe is thought to come mainly from India, though officials say it may also originate in China or Pakistan. Authorities have only discovered a few illegal ketamine labs in Europe, in the Netherlands and Belgium.
Forming a ketamine habit can lead to psychological dependence on the drug, as well as a tolerance that prompts people to take larger – and more dangerous – doses to achieve the same high.
A UK study published in 2012 found that 17 per cent of ketamine users were dependent on it.
However, very few Europeans get treatment for ketamine misuse. In the EU, 600 people got help for problems with ketamine in 2022, up from 240 in 2018.
That could be because while some people take ketamine on its own, others mix it with cocaine or ecstasy, so people with ketamine problems may seek treatment for other drug addictions instead.
Regular ketamine use can damage the bladder, heart, and brain, and cause mental health problems and difficulty breathing.
The same UK study found that 26.6 per cent of recent ketamine users reported urinary tract symptoms.