Optimum Driver

Attention

Drowsy driving: signs and prevention

Being tired slows your reactions, clouds your judgment and can lead to brief sleeps you don't notice. The only real fix for drowsiness is sleep, so the trick is to plan around it.

Why tiredness matters

A tired driver reacts more slowly, misses things at the edges of their view and makes poorer decisions. Worse, a very tired person can fall into microsleeps, brief lapses of a few seconds that they may not even remember. At highway speed, a few seconds is a long way to travel with nobody steering.

Warning signs

  • Yawning often or rubbing your eyes
  • Heavy eyelids or trouble keeping your head up
  • Not remembering the last few miles
  • Missing your exit or a road sign
  • Drifting out of your lane or onto the rumble strip
  • Following too closely without meaning to
  • Restless, irritable feelings and wandering thoughts

If you notice any of these, take them seriously. They mean you're already impaired.

What doesn't fix it

Turning up the radio, opening the window, turning down the heat or singing along may feel like they help, but the effect is short and it doesn't remove the need for sleep. Caffeine can help for a while, but it takes time to kick in and doesn't work the same for everyone. None of these are a substitute for rest.

What to do when you feel tired

  1. 1Find a safe place to stop. A rest area, a well-lit parking lot or a service station. Don't stop on the shoulder unless it's an emergency.
  2. 2Take a short nap. Many sleep experts suggest about 15 to 20 minutes. Give yourself a few minutes to wake up fully before driving again.
  3. 3Swap drivers. If someone else in the car is rested and able to drive, let them.
  4. 4Stop for the night. If you're still drowsy after a break, find somewhere to sleep. A late arrival beats a crash.

Plan long drives around sleep

  • Get a full night's sleep before a long trip.
  • Plan a break about every two hours or 100 miles, even if you feel fine.
  • Avoid driving in the hours when your body expects to sleep, typically late at night and in the early afternoon dip.
  • Share the driving on long trips and agree on when you'll switch.
  • Avoid heavy meals before driving if they make you sleepy.

Medicines and health

Some prescription and over-the-counter medicines cause drowsiness, including some allergy, cold, sleep and pain medicines. Read the label, and ask a pharmacist or doctor whether a medicine is safe to drive on. If you often feel sleepy during the day even after a full night in bed, talk to a doctor. Sleep disorders are common and treatable.

Shift workers and new parents are at higher risk because their sleep is often short or broken. If you've just finished a night shift, consider a nap before driving home, or arrange another way to get there.