Cocaine and ketamine mixed into ‘Calvin Klein’ at Roskilde Festival, expert warns

Researchers from the University of Copenhagen are conducting fieldwork at Roskilde Festival, collecting wastewater samples and interviewing attendees to study drug use during the event and in daily life.

Their findings show rising consumption of both cocaine and ketamine, with the latter increasingly used in combination with other substances, according to Henrik Wigh, a professor at the university’s Department of Criminology.

Ketamine, typically used as an animal anesthetic and occasionally in human surgery, is now being used recreationally across Denmark and Europe to tailor the effects of a high, Wigh said.

A mix of ketamine and cocaine, known as a “summer mix” or “Calvin Klein,” is used to energize a party, while a combination of ketamine and MDMA, called a “winter mix,” produces a more emotional high, he added.

Henrik Rindom, a drug expert, warned of the risks of frequent ketamine use, stating it can destroy the bladder lining and, in severe cases, require a bladder transplant.