In France, the effect that all medicines have on driving performance has been classified into 4 levels of risk, from level 0 (no or negligible risk) to level 3 (major risk) and according to a study by Ludivine Orriols, from Université Victor Segalen, Bordeaux, France, and colleagues, level 2 and 3 medicines are responsible for over 3% of road traffic crashes in France.
The findings of this study, published in this week’s PLoS Medicine, are of international importance because in 2006, the International Council on Alcohol, Drugs and Traffic Safety proposed a classification list based on the French classification system.
The authors identified drivers involved in road traffic crashes in France between July 2005 and May 2008 and used a statistical model to identify factors associated with each driver responsible for a road traffic crash and each driver who was not responsible for a crash.
Overall 72,685 drivers injured in a road traffic crash were part of the study and those who had been prescribed level 2 and level 3 medicines were at higher risk (OR 1.31 and OR 1.25 respectively) of being responsible for the road traffic crash. Furthermore, the authors found that the fraction of road traffic crashes attributable to the use of (prescriptions for) level 2 and 3 medicines was 3.3%.
These results provide strong evidence for the contribution of medicines to the risk of experiencing a road traffic crash and also confirm that the French drug risk classification scheme seems accurate for medicines classified as levels 2 and 3 of risk for road traffic crashes. Therefore, this study reinforces the need for health care workers to provide patients with proper information on the potential effect of any medicine that they are prescribed (or take) on their driving abilities.