Narcolepsy Overview: Causes, Signs and Treatment
Many people think of narcolepsy as the strange and even comical condition that causes sufferers to fall asleep suddenly and at inappropriate times while they’re engaged in other activities. The truth is that narcolepsy is a serious neurological disorder that can have a profound effect on patients’ lives.
A medical condition affecting around 1 in 2,000 people in the United States, narcolepsy can result in a number of negative symptoms, such as excessive daytime sleepiness, sleep paralysis, hallucinations, and even cataplexy, or a loss of muscle control. While symptoms of narcolepsy tend to appear in childhood, it’s often years before patients are diagnosed accurately. Learn more about narcolepsy, what causes the condition, and how it compares to other sleep disorders that affect patients’ health and quality of life.
Causes of Narcolepsy
Doctors don’t know exactly what causes narcolepsy, which occurs with equal frequency in men and women. However, research suggests people with this condition may possess lower levels of a neurochemical known as hypocretin, which regulates REM (rapid eye movement) sleep and wakefulness. An autoimmune reaction may cause the brain to produce less of this important substance.
Additionally, environmental factors could play a role in the development of narcolepsy. Research reveals that exposure to the H1N1 virus, also known as swine flu, could raise an individual’s odds of having the disorder.
The condition may also have a genetic component, as there is some evidence to suggest it runs in families. In rare cases, narcolepsy can result from a traumatic brain injury.
Regardless of the cause, narcolepsy patients enter the REM stage of sleep more quickly. In people with normal sleep cycles, REM begins 60 to 90 minutes after falling asleep. However, individuals with narcolepsy enter this stage within 15 minutes and can experience the dream activity and muscle weakness of REM during times when they’re awake as well.
Without narcolepsy treatment, patients can experience a serious disruption in their work, academic, and social lives.
Narcolepsy Signs and Symptoms
Narcolepsy causes a wide range of symptoms that can affect quality of life. If you’re experiencing one or more of the following symptoms of narcolepsy, don’t hesitate to seek medical treatment:
- Periods of excessive daytime sleepiness (EDS) with typical alertness levels in between; the amount of sleep a person gets does not mitigate EDS.
- Hypnagogic hallucinations (also called hypnopompic hallucinations) that are dream-like experiences that are mainly visual but may involve the other senses.
- Paralysis while falling asleep or waking up, in which a person is conscious but unable to move or communicate.
- Nightmares and sleep disruption.
- Automatic behaviors that the person continues to engage in but without awareness.
People with narcolepsy may also suffer from a sleep disorder known as cataplexy. Causing sudden loss of muscle tone and control, cataplexy may result from strong emotions like fear, humor, or anger. According to the National Institutes of Health, cataplexy is the first symptom to appear in about 10% of narcolepsy patients and is often misdiagnosed as relating to seizures.
While some patients suffer only a couple catalepsy attacks over their lifetimes, others experience repeated occurrences. Cataplexy and narcolepsy are particularly dangerous if attacks occur while patients are driving or engaged in athletic activities.
Diagnosis of Narcolepsy
One of narcolepsy's primary markers, excessive daytime sleepiness, is a common sign of other chronic sleep disorders, such as sleep apnea and idiopathic hypersomnia. To ensure an accurate diagnosis of narcolepsy, doctors will perform specialized tests, as well as a physical exam and in-depth medical history intake.
Physicians use the Epworth Sleepiness Scale test to measure the degree of daytime sleepiness. Made up of eight questions based on a scale from zero (not likely to fall asleep) to three (very likely to fall asleep), the Epworth Sleepiness scale alerts doctors of a narcolepsy red flag for scores above 10.
Two additional tests must be taken before a narcolepsy diagnosis can be given: the polysomnogram (PSG) and the multiple sleep latency test (MSLT).
A PSG is a sleep study test performed in a sleep lab to access nighttime sleep. Your body's responses, such as muscle movement, breathing patterns, and brain activity, are recorded to determine if and what type of sleep disorder you may have.
A multiple sleep latency test is given the morning after the PSG. This test determines the amount of time it takes for someone to fall asleep during the day. Expect to take between four and five short naps every 2 hours. Narcolepsy patients tend to fall asleep in 5 minutes or less, while those with normal sleep patterns take between 10 and 20 minutes.
Your health care practitioner will also ask that you keep a sleep journal that tracks when you wake up, when you go to sleep, and how many and when you take naps.
Treatment of Narcolepsy
While there isn’t a cure for narcolepsy, patients can take medications and adopt lifestyle changes designed to alleviate symptoms.
There are five FDA-approved narcolepsy drug treatments:
- Xyrem (sodium oxybate)
- Provigil (modafinil)
- Nuvigil (amodafonil)
- Methylphenidate
- Amphetamine
Some of the most common narcolepsy treatments include stimulants to help combat excessive sleepiness so patients can avoid sleep attacks. Doctors may prescribe Provigil and Nuvigil as first lines of defense because they are less addictive than the older drugs on the market.
Physicians may also recommend an amphetamine such as Ritalin; however, these drugs often result in unpleasant side effects, such as nervousness and heart palpitations.
Selective serotonin reuptake inhibitors (SSRIs) can be a treatment for narcolepsy. Because they suppress REM sleep, SSRIs can reduce symptoms of cataplexy and mitigate sleep paralysis and hallucinations. Some of the most commonly prescribed SSRIs for narcolepsy sufferers include Prozac and Effexor.
Many narcolepsy patients experience a reduction in symptoms as a result of lifestyle changes. Doctors may recommend that individuals with this condition take several short naps throughout the day, avoid consuming caffeine or alcohol in the evening, and maintain a consistent sleep schedule. Exercising regularly can also help patients improve the quality of their sleep.
Narcolepsy sufferers may also benefit from taking amino acids such as L-tyrosine. According to a study in Medical Hypothesis, narcolepsy may result from dopamine abnormalities. Because L-tyrosine is a precursor of dopamine, patients who take the amino acid may see beneficial results. It is important, however, to take tyrosine with a balanced blend of all essential amino acids to keep blood concentrations stable.
If you’re suffering from narcolepsy or another sleep disorder, talk to your doctor to determine which treatment options are best for you.