Narcolepsy

Narcolepsy has been described as “a funny disease that is no laughing matter” by Marguerite Jones Utley, a writer who also suffers from narcolepsy.  It is not a common illness and usually starts early in life, affecting the sufferer throughout his/her life.  Early diagnosis is essential to prevent serious long-term psychiatric and social consequences. 

Symptoms of Narcolepsy

• Sleepiness is the cardinal symptom of narcolepsy.  Narcoleptics are chronically sleepy and with some effort can remain alert some of the time, but at times may be overwhelmed by their sleepiness (“sleep attacks”). 
• Cataplexy – episodes of muscle weakness that are usually triggered by emotion (more frequently laughter). Its severity varies from person to person and from time to time.  For example, slurred speech, zigzag walking, and buckling at the knees may occur during these episodes.
• Less common symptoms include inability to move as the person is going to sleep or waking up, and vivid dreams that resemble hallucinations.

The Cause of Narcolepsy
Partial or complete absence of a group of cells in the hypothalamus (a part of the brain) causes narcolepsy. These cells manufacture a substance called OREXIN that is involved in the sleep/wake process. OREXIN is a neurotransmitter (neurotransmitters are chemical substances that carry messages between cells in the brain). While this is a mammoth scientific discovery that will hopefully lead to better understanding and treatment of narcolepsy, much remains unknown about this disease.

The Diagnosis of Narcolepsy
The first step is to exclude all other causes of excessive sleepiness. Conditions that can mimic narcolepsy include insufficient sleep and sleep apnea, among others. To exclude those conditions polysomnography is performed. Following polysomnography the patient with suspected narcolepsy is submitted to a series of short naps in a dark room during the day.  Narcoleptics characteristically go to sleep rapidly after the lights are turned off and have a propensity to enter the sleep stage known as rapid eye movement (REM) sleep promptly.  These episodes are called sleep onset REM periods.

Treatment of Narcolepsy

• Adequate sleep duration
• Strategic naps
• Support groups
• Medications

The conventional medications have been Ritalin (methylphenidate), Cylert (pemoline), and amphetamines. These are central nervous system stimulants.

Modafinil (Provigil), a non stimulant, has recently become the treatment of choice for the sleepiness of narcolepsy. It is simpler to use and has less side effects than the stimulants.

Certain antidepressants are effective in the treatment of cataplexy and are often prescribed along with the medications mentioned above.

Sodium oxybate (Xyrem) is the newest medication for the treatment of cataplexy. It appears to help as well with excessive sleepiness. It induces deep sleep rapidly. It is supplied by a central pharmacy and must be requested using a special form. It must be administered at night in two divided doses.

Contact
For more information on narcolepsy please contact the Scott & White Sleep Disorders Center at 254-724-3227.