A study examining the effectiveness of colour-graded pictogram labels has concluded that they don’t work to reduce medicine-related traffic crashes.
The study, published in the British Journal of Clinical Pharmacology, examined whether the pictograms used in France on medicines labelling, which indicate whether it is safe to drive while taking a medicine, are linked to a reduction in traffic accidents in people taking the medicines.
The pictogram system has three levels: yellow for “be careful,” orange for “be very careful” and red for “do not drive”.
A team led by Ludivine Orriols, and Emmanuel Lagarde, of the University of Bordeaux analyzed information from three French national databases and matched it to the national health care insurance database, police reports, and the national police database of injurious crashes.
The three drug classes considered were those with the most consistent evidence for a causal association with the risk of road traffic crashes: benzodiazepine anxiolytics, benzodiazepine hypnotics, and z-hypnotics.
Use of benzodiazepine anxiolytics was associated with a 42% increased likelihood of being responsible for a road traffic crash during the pre-intervention period.
The increased risk disappeared after introduction of the pictogram but became significant again in later time periods (19% and 35% increased risks in the third and fourth periods studied, respectively).
This trend was similar for benzodiazepine hypnotics, although fewer individuals took these drugs, making the results insignificant.
Even worse, the risk of being responsible for a crash increased in users of z-hypnotics across the study period (with 24, 32, and 32% increased risks in periods 2, 3, and 4, respectively).
The findings question the efficacy of the measure for promoting awareness about the effect of medicines on driving abilities, the authors say.
“We estimated that medicinal drug consumption is responsible for around three percent of road traffic crashes,” says Dr Orriols.
“Prevention policies should be revisited towards the general driving population but also towards healthcare professionals, including general practitioners and pharmacists,” says Dr Lagarde.