A Prescription for Dangerous Driving

According to a recent study, drivers taking certain types of prescription drugs are more likely to be involved in a traffic accident.

The study, which was published in the online medical journal PLoS Medicine, was conducted in France where medical experts classify all prescription medications into one of four levels based on their risk of driving impairment.  Drugs classified as level 0 have little to no risk of driving impairment, while drugs classified as level 1, 2, or 3 have increasing risk of impairment.  Level 3 drugs carry major risk of impairment.

The study looked at all vehicle crashes between July 2005 and May 2008 that resulted in someone being injured and compared prescription drug use by those who were responsible for the accident to those who were not responsible.  The researchers found that that the risk of causing an accident resulting in injury increased by 1.24 to 1.40% for drivers who used at least one level 2 or level 3 medication.  The researchers also found that the risk of being responsible for an accident increased as the number of level 2 or 3 medications prescribed to a driver likewise increased.

Level 2 medications strongly associated with increased risk of driver culpability in injurious accidents:

• alcoholic-dependence drugs
• anti-dementia drugs
• antidepressants (most commonly selective serotonin reuptake inhibitors or SSRIs such as PROZAC or PAXIL)
• antipsychotics (certain ones)
• anti-seizure drugs
• anxiolytics (tranquilizers, predominantly benzodiazepines)
• opioid-dependence drugs

Level 3 medications strongly associated with increased risk of driver culpability in injurious accidents:

• antipsychotics (certain ones)
• anxiolytics (certain ones)
• hypnotics/sedatives
• opioids (certain ones)

Medications can impair driving ability in different ways.  Some medications make you drowsy or impair judgment or reaction time.  In addition, some diabetes drugs can cause hypoglycemia, which may lead to seizures or loss of consciousness.

The United States does not classify drugs according to the their risk of impairment, so Americans need to make sure they are not driving while using a prescription drug that may put them at a higher risk of causing an accident.  If you are taking prescription medications, make sure to ask your doctor if the drug could affect your ability to operate a motor vehicle.  You can also ask your pharmacist for a medication guide or view one on the FDA’s website.   The U. S. Department of Transportation, National Highway Traffic Safety Administration was also authored a comprehensive study on the effects of prescription drug use in elderly drivers which can be accessed at NHTSA