Excessive Daytime Sleepiness

What is excessive daytime sleepiness?

Excessive daytime sleepiness (EDS) is a sleep disorder. People who have EDS feel very drowsy during the day and have an overwhelming urge to fall asleep, even after getting enough nighttime sleep. They often doze, nap, or fall asleep when they need or want to be awake and alert. This can be dangerous when driving a car or operating machinery. This disorder is also called hypersomnia or somnolence.

What is the cause?

Excessive daytime sleepiness is not caused by lack of sleep. If you feel tired or sluggish during the day because you are not getting a normal amount of sleep, you do not have EDS. EDS is usually caused by a physical condition such as:

• a tumor, head trauma, or injury to the central nervous system
• another sleep disorder such as narcolepsy or sleep apnea
• medicines such as tranquilizers and sleeping pills
• drug or alcohol abuse
• heredity
• withdrawal from caffeine, alcohol, or stimulants

Medical conditions such as multiple sclerosis, depression, encephalitis, epilepsy, or obesity may contribute to the disorder. Sometimes there is no known cause.

EDS is most common in teenagers and young adults.

What are the symptoms?

Symptoms include:

• constant sleepiness
• frequent napping
• long nighttime sleeping
• irritability
• mild depression
• memory loss
• lack of concentration

People with this disorder may feel frustrated and angry because others think they are lazy or uninterested. EDS may cause problems in the workplace and with family and friends.

How is it diagnosed?

If you sleep poorly for a month or more, or if you find sleepiness during the day interferes with normal tasks, see your healthcare provider. You may be asked to visit a sleep center so your sleep can be monitored.

The most common test for EDS is a polysomnogram. This test is not painful. Before you go to sleep, dime-sized sensors are placed on your head and body. The sensors record brain waves, muscle activity and movement, heartbeat, and breathing

You may also be given the multiple sleep latency test (MSLT). This test shows how quickly you fall asleep, a good measure of daytime sleepiness. For the MSLT, you will be asked to take several naps during the test period.

You might also have the maintenance of wakefulness test (MWT). The MWT is similar to an MSLT except that you stay awake instead of napping during the test.

How is it treated?

Your treatment depends on what is causing the EDS. If it is caused by a medical condition, treating the medical condition may take care of the sleep problem. If it is caused by medicines, your dosage or prescription may be adjusted. You may be prescribed stimulant medicine or medicine to improve sleep at night. Lifelong treatment may be needed.

For more information, contact:

National Sleep Foundation
Phone: 202-347-3471
Web site: http://www.sleepfoundation.org