This year saw a rise in drivers under the influence of multiple drugs, according to the National Institute of Criminology and Criminalistics (INCC).
Out of 8,289 saliva samples from drivers testing positive for drugs in 2025, more than one drug was detected in 30% of cases.
Cannabis and cocaine are the most common combination, accounting for 54% of cases.
The INCC highlights that consuming multiple drugs significantly heightens the risk of severe injury or death. Cannabis doubles this risk, while substances like amphetamines can increase it by 5 to 30 times.
Poly-drug use among drivers has risen from 20% in 2020 to 30% in 2025, according to the institute.
Sarah Wille, head of forensic toxicology at the INCC, notes a clear shift towards both drug combinations and newer substances, which pose growing road safety challenges.
Some substances, including ketamine and certain synthetic drugs, are not always detected by standard saliva tests during traffic checks.
However, these substances can be identified during laboratory analyses. Ketamine, increasingly found in cases of driving under the influence, requires greater attention, says the INCC.
Ketamine accounts for around 6% of cases, equating to nearly 500 incidents annually.
