Narcolepsy is a chronic sleep disorder characterized by overwhelming daytime drowsiness and sudden attacks of sleep. People with narcolepsy often find it difficult to stay awake for long periods of time, regardless of the circumstances. Narcolepsy can cause serious disruptions in your daily routine.
Narcolepsy is a chronic condition for which there's no cure. However, medications and lifestyle changes can help you manage the symptoms. Talking to others — family, friends, employer, teachers — can help you cope with narcolepsy.
Skip to one of the following sections:
- What are Symptoms of Narcolepsy?
- What Causes Narcolepsy?
- What Narcolepsy Treatments are Available?
- Preparing for Your Appointment
What are the Symptoms of Narcolepsy
Symptoms of narcolepsy may worsen for the first few years, and then continue for life. They include:
- Excessive daytime sleepiness. The primary characteristics of narcolepsy are overwhelming drowsiness and an uncontrollable need to sleep during the day. People with narcolepsy fall asleep without warning, anywhere, anytime. For example, you may suddenly nod off while working or talking with friends. You may sleep for a few minutes or up to a half-hour before awakening and feeling refreshed, but eventually you fall asleep again. You also may experience decreased alertness throughout the day. Excessive daytime sleepiness usually is the first symptom to appear and is often the most troublesome, making it difficult for you to concentrate and function fully.
- Sudden loss of muscle tone. This condition, called cataplexy, can cause a number of physical changes, from slurred speech to complete weakness of most muscles, and may last for a few seconds to a few minutes. Cataplexy is uncontrollable and is often triggered by intense emotions, usually positive ones such as laughter or excitement, but sometimes fear, surprise or anger. For example, your head may droop uncontrollably or your knees may suddenly buckle when you laugh. Some people with narcolepsy experience only one or two episodes of cataplexy a year, while others have numerous episodes daily.
- Sleep paralysis. People with narcolepsy often experience a temporary inability to move or speak while falling asleep or upon waking. These episodes are usually brief — lasting one or two minutes — but can be frightening. You may be aware of the condition and have no difficulty recalling it afterward, even if you had no control over what was happening to you. This sleep paralysis mimics the type of temporary paralysis that normally occurs during rapid eye movement (REM) sleep, the period of sleep during which most dreaming occurs. This temporary immobility during REM sleep may prevent your body from acting out dream activity. Not everyone with sleep paralysis has narcolepsy, however. Many people without narcolepsy experience some episodes of sleep paralysis, especially in young adulthood.
- Hallucinations. These hallucinations, called hypnagogic hallucinations, may occur when falling quickly into REM sleep, as you do when you first fall asleep, or upon waking. Because you may be semiawake when you begin dreaming, you experience your dreams as reality, and they may be particularly vivid and frightening.
People with narcolepsy may have other sleep disorders, such as obstructive sleep apnea, in which breathing starts and stops throughout the night, restless legs syndrome and even insomnia. People with narcolepsy may also act out their dreams at night by flailing their arms or kicking and screaming.
Some episodes of sleep attacks are brief, lasting seconds. Some people with narcolepsy experience automatic behavior during these brief episodes. For example, you may fall asleep while performing a task you normally perform, such as writing, typing or driving, and you continue to function while asleep. When you awaken, you can't remember what you did, and you probably didn't do it well. For instance, if you were writing, what you wrote asleep may look like scribbling.
The signs and symptoms of narcolepsy can begin anytime up to your 50s, but they most commonly begin between the ages of 10 and 25. Symptoms often are more severe for those who develop them early in life, rather than in adulthood.
When to See a Doctor
See your doctor if you experience excessive daytime sleepiness that disrupts your personal or professional life.
What Causes Narcolepsy?
The exact cause of narcolepsy isn't known. Genetics may play a role. Other factors, such as infection, stress or exposure to toxins, may contribute to the development of narcolepsy.
Contrary to what some people believe, narcolepsy isn't related to depression, seizure disorders, fainting, simple lack of sleep or other conditions that may cause abnormal sleep patterns.
Normal Sleep Pattern vs. Narcolepsy
The normal process of falling asleep begins with a phase called non-rapid eye movement (NREM) sleep. During this phase, your brain waves slow considerably. After an hour or two of NREM sleep, your brain activity picks up again, and REM sleep begins. Most dreaming occurs during REM sleep.
The Role of Brain Chemicals
Hypocretin is an important chemical in your brain that helps regulate wakefulness and REM sleep. People with narcolepsy have low levels of this neurochemical in their spinal fluid. It's particularly low in those who experience cataplexy. Exactly what causes the loss of hypocretin-producing cells in the brain isn't known, but experts suspect it's due to an autoimmune reaction.
What Narcolepsy Treatments are Available?
There is no cure for narcolepsy, but medications and lifestyle modifications can help you manage the symptoms.
Medications for narcolepsy include:
- Stimulants. Drugs that stimulate the central nervous system are the primary treatment to help people with narcolepsy stay awake during the day. Doctors often try modafinil (Provigil) first for narcolepsy because it isn't as addictive as older stimulants and doesn't produce the highs and lows often associated with older stimulants. Side effects of modafinil are uncommon, but they may include headache, nausea, dry mouth, anorexia and diarrhea. Modafinil may increase blood pressure, especially at high doses. Some people need treatment with methylphenidate (Concerta, Ritalin, others) or various amphetamines. Although these medications are effective, they may cause side effects, such as nervousness and heart palpitations, and can be addictive.
- Selective serotonin or norepinephrine reuptake inhibitors (SSRIs, SNRIs). Doctors often prescribe these medications, which suppress REM sleep, to help alleviate the symptoms of cataplexy, hypnagogic hallucinations and sleep paralysis. They include atomoxetine (Strattera), fluoxetine (Prozac, Sarafem, others) and venlafaxine (Effexor). The most common side effects include decreased sexual desire and delayed orgasm. Other side effects may wane over time. They can include digestive problems, jitteriness, restlessness, headache and insomnia.
- Tricyclic antidepressants. These older antidepressants, such as protriptyline (Vivactil) and imipramine (Tofranil), are effective for cataplexy, but many people complain of side effects, such as dry mouth and constipation.
- Sodium oxybate (Xyrem). This medication may be prescribed for severe cataplexy. Sodium oxybate helps to improve nighttime sleep, which is often poor in narcolepsy. In high doses it may also help control daytime sleepiness. It must be taken in two doses, one at bedtime and one up to four hours later, and it can take two to three months to achieve its full effect, although benefits will be apparent early on. Xyrem can have serious side effects, such as nausea, bed-wetting and worsening of sleepwalking. Too high a dose can lead to difficulty breathing, coma and death.
If you have other health problems, such as high blood pressure or diabetes, ask your doctor how the medications you take for your other conditions may interact with those taken for narcolepsy.
Certain over-the-counter drugs, such as allergy and cold medications, can cause drowsiness. If you have narcolepsy, your doctor will likely recommend that you avoid taking these medications.
Preparing for Your Appointment
You're likely to start by seeing your family doctor or a general practitioner. However, in some cases when you call to set up an appointment, you may be referred immediately to a sleep specialist.
Information to Gather in Advance
- Write down your symptoms, when they first started and when they tend to occur.
- Write down your key medical information, including other conditions with which you've been diagnosed and any prescription or over-the-counter medications you're taking, including vitamins and supplements. Also note whether you or anyone in your family has a history of restless legs syndrome.
- Take a family member or friend along, if possible. Sometimes it can be difficult to soak up all the information provided to you during an appointment. Someone who accompanies you may remember something that you missed or forgot.
- Write down questions to ask your doctor. Creating your list of questions in advance can help you make the most of your time with your doctor.
Below are some basic questions to ask your doctor about narcolepsy. If any additional questions occur to you during your visit, don't hesitate to ask.
- What is the most likely cause of my signs and symptoms?
- Are there any other possible causes?
- What tests are needed to make a diagnosis?
- What treatment options are available for this condition?
- If you're recommending medications, what are the possible side effects?
- I have these other health conditions. How can I best manage them together?
- What self-care steps are likely to improve my symptoms?
- Can you recommend any educational materials for me to take home or look up on the Web?
- Where can I find a support group for people with sleep disorders?
What to Expect from Your Doctor
Your doctor is likely to ask you a number of questions.
Your doctor may make a preliminary diagnosis of narcolepsy based on your excessive daytime sleepiness and sudden loss of muscle tone (cataplexy). After an initial diagnosis, your doctor may refer you to a sleep specialist for more evaluation.
Formal diagnosis may require staying overnight at a sleep center, where you undergo an in-depth analysis of your sleep by a team of specialists.