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Excessive Daytime Sleepiness

Excessive Daytime Sleepiness

Falling asleep at inappropriate times, such as while eating, talking, or driving, is a sign of excessive daytime sleepiness.

Excessive daytime sleepiness can have serious consequences, such as:

  • Car crashes. Sleepiness may be the main cause of over one-third of all fatal traffic accidents and as many as one-half of all traffic accidents.
  • Poor school performance. Sleepiness can cause impaired learning, perceptual skills, and memory, which may lead to poor school performance and grades.
  • Work-related accidents. Sleepiness on the job causes performance errors and increases the risk of accidents.

The most common cause of daytime sleepiness is not allowing enough time for a full night's sleep (chronic sleep deprivation)—the demands of our schedules dictate that we wake up to an alarm, not when we are fully rested, and we often stay up long after our body tells us it needs to sleep. Shift workers and teens have a particularly high risk of chronic sleep deprivation.

How much sleep a person needs varies with age and from person to person. The number of hours you sleep is not as important as how you feel when you wake up. If you do not feel refreshed, you probably need more sleep. Feeling tired during the daytime is another sign you are not getting enough sleep. Many times, simple home treatment can help you get the sleep you need.

Excessive daytime sleepiness may indicate you have a sleep disorder, such as sleep apnea or narcolepsy.

If you have tried home treatment and still have excessive daytime sleepiness, call your doctor to evaluate your symptoms.


ByHealthwise Staff
Primary Medical ReviewerWilliam H. Blahd, Jr., MD, FACEP - Emergency Medicine
Specialist Medical ReviewerDavid Messenger, MD
Last RevisedNovember 27, 2012

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