How can I tell if I am too tired to drive?

There is no "drowsiness test" to measure if you are too tired to drive. Research shows that people often overestimate their level of alertness. So you may be drowsier than you think you are!

This content originally appeared on the American Academy of Dental Sleep Medicine (AADSM) website.
Driving while drowsy is very dangerous. The U.S. National Highway Traffic Safety Administration estimates that drowsy driving accounts for 1,500, or 4%, of total traffic fatalities annually. Studies have shown that drivers cannot accurately rate their degree of impairment due to drowsiness and that sleep-related accidents are more common in young people than in the elderly. Warning signs that you are too tired to drive include: trouble keeping your eyes open, trouble keeping your head up, daydreaming or wandering thoughts, drifting across lanes, drifting off the road or hitting rumble strips, missing signs or exits, frequent yawning or rubbing your eyes, and irritability or restlessness. If you are drowsy or falling asleep while driving, stop and take a nap. Cold air and loud music are not effective in keeping you awake.
Ever have trouble remembering the last few turns you made? If so, you might want to pull over. It could be a sign that you're too drowsy to drive.

Drowsy driving leads to an eightfold increase in the risk of injury or death from a car crash, according to sleep research. But not everyone is good at recognizing the signs of sleep deprivation.

Yes, tired eyes, constant yawning, a foggy brain and a nodding head are clear signs that you're sleepy -- too sleepy to drive safely. But here are a few other less obvious clues you have highway hypnosis:
  • Frequent squinting and blinking
  • Missed streets or exits
  • Difficulty picturing previous turns or stretches of road

If you ever experience any of these situations while driving, pull over, park and grab a catnap in a safe place.

Driving while drowsy is far more common -- and dangerous -- than you might think. In a recent poll, it was revealed that 60% of Americans reported driving while sleepy in the previous year. And 37% confessed to actually nodding off. Yikes! Researchers suspect many motorists simply don't recognize the signs that they're too drowsy to safely drive. Or worse, assume they can stay awake anyway. But feeling sleepy is just as dangerous as being sleep deprived, research shows. Both are associated with a dramatic increase in crash-related critical injuries or death.

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Important: This content reflects information from various individuals and organizations and may offer alternative or opposing points of view. It should not be used for medical advice, diagnosis or treatment. As always, you should consult with your healthcare provider about your specific health needs.