Narcolepsy symptoms include excessive sleepiness and random muscle paralysis. Fortunately, this challenging sleep disorder can be controlled with medication, enabling patients to live productive lives.
Narcolepsy is a chronic sleep disorder caused by the brain’s inability to regulate a normal sleep-wake cycle. If you have narcolepsy, you may fall asleep quickly at inappropriate times of the day and wake up during the night when you want to sleep.
“People with narcolepsy are constantly slipping between being awake and REM [dream] sleep,” explains Lisa Shives, MD, founder of North Shore Sleep Medicine in Evanston, Ill. “Not only does sleep intrude on their wakefulness, but wakefulness intrudes on their sleep.”
Narcolepsy is estimated to affect about one in every 2,000 Americans — men and women equally. It typically starts in the teen years or early twenties. If left untreated, narcolepsy can be extremely disabling. However, says Dr. Shives, “We have good medications that can help a person with narcolepsy live a normal life.”
The Mystery of Narcolepsy
The exact cause of narcolepsy remains unknown, but researchers believe that a deficiency in the wakefulness-promoting neurotransmitter, hypocretin, may be to blame. Genetics may also play a role.
“We know there is a mild increased risk [of narcolepsy] if you have a first-degree relative with the condition, but there is an environmental component, too,” says Shives. Environmental factors that may trigger narcolepsy include infection, problems with the immune system, trauma, hormonal changes, and stress.
Symptoms You May Experience
Four common symptoms are associated with narcolepsy:
- Excessive daytime sleepiness. People with narcolepsy are almost always tired, regardless of how much sleep they get at night, and they may have “sleep attacks,” in which they fall asleep during the day at inappropriate times and without warning. These sleep attacks can last anywhere from a few minutes or less to hours, and can be dangerous if they occur while driving a car.
- Cataplexy. An emotional reaction, such as excitement, anger, surprise, fear, or laughter, can trigger cataplexy, a sudden loss of muscle control ranging from slight weakness to total collapse; this may last from 30 seconds to a few minutes. The severity of the attack can vary — you may become mildly limp, drop something you’re holding, or completely fall to the ground. Someone having a cataplectic attack is unable to talk, but is fully conscious. Three out of four people with narcolepsy experience cataplexy.
- Sleep paralysis. Sometimes people with narcolepsy are unable to talk or move for about one minute when falling asleep or waking up.
- Hallucinations. Many people with narcolepsy experience dream-like hallucinations in which they hear sounds or see visions when falling asleep or, less often, when awakening.
Disrupted sleep is also common in people with narcolepsy, as are leg jerks, restlessness, and nightmares.
By Hedy Marks, MPH – Medically reviewed by Pat F. Bass III, MD, MPH