Narcolepsy

What is narcolepsy?

Narcolepsy is a disorder that causes sudden, uncontrollable urges to sleep. People with this disorder may fall asleep without any warning for several minutes or an hour at a time. They may have just a few sleep attacks, or many attacks in a single day. Sleep attacks may happen after meals, or while talking, working, driving a vehicle, reading, or watching TV.

Narcolepsy usually starts between ages 15 and 30, but may begin at any age. Once it starts, this disorder is lifelong.

What is the cause?

The cause of this disorder is not known. It may be caused by a shortage of a brain-stimulating protein called orexin. People with narcolepsy may have fewer nerve cells, called hypocretin neurons, in the brain. Other possible causes may include autoimmune disease, brain injury, and infection.

Your risk is greater if another family member has narcolepsy.

What are the symptoms?

Symptoms may include:

• Sleep attacks. The desire to sleep cannot be resisted. These attacks are brief, lasting only 5 to 10 minutes. The attacks can occur many times a day.
• Cataplexy. This is a sudden loss of muscle tone that may cause people to fall to the floor. It is brought on by laughter, stress or other intense emotions.
• Hallucinations. Seeing or hearing things that are not real, that may occur when falling asleep or waking up.
• Sleep paralysis. This is being unable to move or speak for a short time when falling asleep or waking up.

How is it diagnosed?

Your healthcare provider will examine you and ask about:

• your sleep patterns
• use of caffeine, alcohol, medicine, and other drugs
• eating and exercise habits
• your medical and mental health history
• your family history
• your job and travel patterns

Your healthcare provider may also ask your family members about your sleep habits. A blood sample may be taken for lab tests.

Your provider may refer you to a sleep center. At the sleep center you may have a continuous, all-night recording of your breathing, eye movements, muscle tone, blood oxygen levels, heart rate and rhythm, and brain waves.

How is it treated?

Medicines and lifestyle changes may reduce the symptoms. Sleep paralysis and cataplexy may be treated with certain antidepressants. Excessive daytime sleepiness may be treated with stimulants. It also helps to take regularly scheduled short naps during the day.

Not all excessive sleepiness is caused by narcolepsy. If sleepiness during the day interferes with normal tasks, see your healthcare provider.

For more information about narcolepsy and sleep disorders, contact the National Sleep Foundation at 202-347-3471 or visit their Web site at http://www.sleepfoundation.org.