7 warning signs that you're too tired to keep driving

Fatigued drivers cause an estimated 100,000 crashes on Americas roads each year. And that's just a conservative guess by The National Highway Traffic Safety Administration .

Those crashes claim the lives of 1,500 people and injure another 71,000.

Here are the 7 warning signs from the National Sleep Foundation that you need to pull over and rest:

• Difficulty focusing, frequent blinking, or heavy eyelids
• Daydreaming; wandering/disconnected thoughts
• Trouble remembering the last few miles driven; missing exits or traffic signs
• Yawning repeatedly or rubbing your eyes
• Trouble keeping your head up
• Drifting from your lane, tailgating, or hitting a shoulder rumble strip
• Feeling restless and irritable

Here are some tips on how you can combat fatigued driving and fall-asleep crashes.

Sources:  DrowsyDriving.org , National Sleep Foundation