A chart from the European Union Drugs Agency (EUDA) that ranked Namur sixth among European cities for ketamine found in wastewater in 2025 has been widely shared on social media. Experts warn, however, that the ranking should be read carefully.

Seven of the 20 cities on the chart are Belgian. Namur comes in sixth, behind party hotspots such as Amsterdam, Berlin, Bristol, which tops the list by a wide margin. Namur ranks ahead of Antwerp, Brussels, and Liège.

According to EUDA Belgian, German and Dutch cities had the EU's highest levels in 2025; loads rose 41% from 2024 to 2025.

However, it's important to note that the comparison is lopsided, as Belgium monitors its sewage far more extensively than most of its neighbours. The more Belgian sites are sampled, the more of them can make the list, which explains why 17 Belgian cities are included in the data, compared to only six Dutch cities and a single French one.

Caution over Namur

Sciensano, Belgium’s public health institute, told La Dernière Heure it was wary of singling out the city.

"Ketamine has been detected at all but one sampling site in Belgium, with no particular region showing consistently higher levels of consumption." They said. "We must therefore take margins of error into account before concluding that Namur is the municipality with the highest levels of ketamine in Belgium."

Namur police take a similar view. Though ketamine seizures in the Walloon capital have risen, the drug remains a minor concern compared with cocaine and cannabis.

What is ketamine?

Ketamine, also known as 'K’, ‘ket', or 'special K', was developed in the 1960s as an anaesthetic. It is still widely used in human and veterinary medicine and features on the World Health Organization's list of essential medicines.

In recent years, low doses of ketamine have also been used to treat depression that does not respond to other treatments. Taken recreationally, it produces powerful dissociative and hallucinogenic effects.

"These are people who are a bit like zombies, doing all sorts of things," said Jean-Michel Dogné, Dean of the Faculty of Medicine at the University of Namur.

"It has an antidepressant effect, creates withdrawal symptoms, difficult comedowns and long-term depression. It is also hallucinogenic and ‘suicidogenic’. Some have jumped out of windows thinking they could fly," he said.

Sharp rise since Covid

Use of Ketamine has soared since the pandemic, particularly among 16- to 30-years-olds.

“We noticed a surge between 2020 and 2021,” said Caroline Grimard, youth services coordinator at Phénix, a day centre for drug users in Namur. “In the space of a year, ketamine has gone from 2 per cent of secondary use to 7 per cent of primary use, with an average age of 17.”

National figures tell the same story. Between 2012 and 2023, ketamine levels in Belgian wastewater rose between seven-and elevenfold, depending on the site.

In 2025, treatment centres recorded 602 episodes with ketamine as the primary substance, up from just 32 a decade earlier.

Cheap and easy to find

Price also plays a role: "A gram of ketamine costs around 20 to 40 euros, well below the price of cocaine. It appeals to a younger demographic with less purchasing power," Dogné said.

Many users also take it during the week, away from parties, specifically to reach a dissociative state.

The health consequences can be severe. Ketamine is known to damage the bladder and kidneys, sometimes irreversibly.

"It’s a scourge; it causes significant harm," Grimard said. "We’ve treated 16-year-olds with severely damaged kidneys, forced to wear a urine bag after several months of heavy use."

Deeper causes

With the port of Antwerp and the Dutch ports close by, Belgium is a major drug-trafficking hub, and wastewater figures do not measure consumption alone.

"Some of the ketamine is flushed down the toilet without being consumed – out of fear of the police, for example," Dogné said. "The more of it circulating in a region, the greater the spillover effect.” Legitimate medical and veterinary use, by contrast, is “likely to have only a minor influence," he added.

However, Dogné and the Phénix team see the levels in Namur as a symptom of a national trend rather than a local anomaly. Rising poverty, worsening mental health among young people, the spread of drug trafficking, and cuts to the care and voluntary sectors all play a part.

"It’s difficult as a politician to make the case that more resources are needed for drug users," Dogné said, "but we will never solve the problem of addiction by cutting funding for those who treat them."

Phénix's youth service has run on the same budget since 2015, with no indexation. The number of young people coming through its doors has kept growing all the same.

If you or someone you know is struggling with drug use, contact Druglijn (078 15 10 20, Dutch) or Infor-Drogues (02 227 52 52, French).