Drowsy Drivers

Every year, falling asleep while driving is responsible for at least 100,000 automobile crashes, 40,000 injuries, and 1550 fatalities. Crashes included in this category happen between midnight and 6 a.m. They  involve a single vehicle and a sober driver traveling alone, with the car leaving the roadway without any attempt to avoid the crash. These figures underestimate the true level of involvement of drowsiness because they do not include crashes involving daytime hours, multiple vehicles, alcohol, passengers, or evasive maneuvers.

Typically, crashes related to sleepiness have the following characteristics: 

  • The problem occurs during late night/ early morning or midafternoon.
  • The crash is likely to be serious. 
  •  A single vehicle leaves the roadway. 
  • The crash occurs on a high-speed road. 
  • The driver does not attempt to avoid a crash. 
  • The driver is alone in the vehicle.

Sleep-related crashes usually occur when motor vehicles are being piloted by drivers who are:

  • Drug Induced -- Sometimes drowsy drivers are people who have taken medication -- over-the-counter or prescribed -- who have become affected by the drug. Common prescription drugs that may have that affect include medications taken for allergies, pain, diabetes, high blood pressure, cholesterol, ulcers, depression, anxiety disorders, and insomnia. Over-the-counter drugs may include cold medicines, antihistamines, motion sickness drugs, pain relievers, decongestants, and diuretics.
  • Each of these drugs comes with a warning label that indicates it may cause drowsiness. You should not drive while taking a medication that advises against operating heavy machinery. It is important to understand before you get behind the wheel of a vehicle how any drug you are taking is going to affect your reaction time, concentration, and vision. 
  • Sleep Deprived -- Sometimes a drowsy driver is just someone who hasn't had enough sleep and their bodies are sleep deprived. Continuing to drive when your body needs sleep can cause you to  be unable to focus on the task of driving, your reaction times are increased, and the chances of your causing a crash are also greatly increased.
  • Untreated or Undiagnosed Sleep Disorders -- especially sleep apnea syndrome (SAS) and narcolepsy. 
  • Consumption of Alcohol -- which interacts with and adds to drowsiness.   
  • Driving Patterns -- including driving between midnight and 6 a.m.; driving a substantial number of miles each year and/or a substantial number of hours each day; driving in the midafternoon hours (especially for older persons); and driving for longer times without taking a break.

The National Highway Transportation Safety Association has developed a program to combat drowsy driving which employs both educational and technological solutions. Education programs are directed toward specific subpopulations as well as the general driving public. Current educational efforts to combat drowsy driving are directed at shift workers and college students, using social marketing approaches to determine appropriate messages and delivery mechanisms. Programs increase awareness of the need for sleep and provide information on how to get better quality sleep, how to recognize when a driver is fighting sleep, and what to do when the driver is too sleepy to drive.

But perhaps the best advice is when you start feeling sleepy, pull over. Don't think you are going to control your sleepiness. If you continue driving when you are sleepy, you may actually fall asleep at the wheel and disaster is impending.

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