Illicit drugs in Emergency Department patients injured in road traffic accidents.

Urine and blood samples from 1730 drivers involved in road accidents (July 2012 - December 2015) were analyzed for the evaluation of driving under influence of drug of abuse according to the Lombardia Region guideline. The 22.5% (95% CI 20.5 to 24.5) of urine screenings tested positive for at least one class of drugs. 10.6% (95% CI 9.2 to 12.1) of the 1730 drivers were under the influence of drug, being blood concentration above the cut-off limit for at least one active substance; the proportion of illicit drugs in blood was cocaine 5.7 % (95% CI 4.7 to 6.9), cannabinoids 3.7 % (95% CI 2.9 to 4.7), opiates 1.4% (95% CI 0.9 to 2.1), methadone 1.4% (95% CI 0.9 to 2.1), amphetamines 0.2% (95% CI 0.04 to 0.5). Trend in proportion showed similar percentage (about 5%) of cocaine and cannabinoids consumption in the last two years. Poly-drug of abuse consumption emerged in the 10.4% (95% CI 6.4 to 15.7) of the positive blood and alcohol was above the legal limit in 47% (95% CI 39.6 to 54.5) of the subjects driving under the influence of drugs.