Everything You Need to Know About Narcolepsy
You’re sleepy day in and day out, with an uncontrollable urge to sleep at your desk even though you thought you slept well the night before. It could be narcolepsy, a condition in which the sleep-wake cycle isn’t properly controlled. The National Institute of Neurological Disorders and Stroke says that between 135,000 and 200,000 people in the U.S. suffer from this condition each day. What happens in narcolepsy and what can be done about it?
What is narcolepsy?
Narcolepsy is a condition in which a person has overwhelming sleepiness during the day. Someone with narcolepsy may uncontrollably and unexpectedly fall asleep, even in the middle of activities such as eating or talking. Those with narcolepsy are at high risk of injury when they become sleepy.
Narcolepsy is caused by a disturbance in the natural sleep-wake cycle within the brain, and it can last a lifetime. In addition to daytime sleepiness, people with narcolepsy also have poor sleep at night. They often wake up at night and are unable to go back to sleep. It’s important to note that people with narcolepsy do not necessarily sleep more in 24-hours than those without the condition.
What are the signs and symptoms of narcolepsy?
Since narcolepsy is a disruption of the normal sleep-wake cycle, people with narcolepsy experience problems with sleepiness when awake and problems with wakefulness during sleep. All people diagnosed with narcolepsy have significant sleepiness during the day, and up to a third will have all of the other symptoms listed here.
Excessive daytime sleepiness – the hallmark of narcolepsy experienced by all people with the diagnosis
Sleep attacks – falling asleep suddenly during the day
Cataplexy – muscle weakness triggered by strong emotions like laughter or anger, which may cause the person to collapse. Unlike in seizure, people with cataplexy are fully conscious during an episode.
Sleep paralysis – losing the ability to move or speak when waking up or falling asleep
Hallucinations when falling asleep – seeing, hearing, or feeling things that aren’t real before sleep
Fragmented sleep – frequently waking up during sleep and trouble falling back asleep once awake
What causes narcolepsy?
Narcolepsy symptoms typically develop in people in their teens and twenties. Most people who have narcolepsy Type 1 have a deficiency in hypocretin. This brain hormone helps to control wakefulness and aids in REM sleep regulation. It’s not fully understood why this deficiency occurs, but it may be due to any of the following factors:
Family history of narcolepsy – only about 10 percent of people with narcolepsy Type 1 have a close relative with the condition
Autoimmune disorders – in which the body’s immune system turns against itself. Researchers believe a combination of genetic or environmental factors may lead to the immune system’s destruction of the brain’s hypocretin
Brain damage – in rare cases traumatic brain injury, stroke, or tumors can lead to narcolepsy
Types of Narcolepsy
The ICD 10 code for a diagnosis of narcolepsy is G47.4. The diagnosis can be further specified by which type of narcolepsy a person has based on his or her symptoms.
- Narcolepsy Type 1 – In this form, a person has a combination of at least 3 months of excessive daytime sleepiness plus either cataplexy or low levels of the brain hormone hypocretin-1, or both.
- Narcolepsy Type 2 – Those with this form will have a constant level of excessive sleepiness for at least 3 months, but they do not experience cataplexy. People with narcolepsy Type 2 have normal levels of the brain chemical hypocretin-1, and they do not have another sleep disorder that explains their symptoms.
Narcolepsy Type 1 is considered the more severe form of the condition, though both can be debilitating and require treatment.
Narcolepsy Tests
A person with excessive sleepiness during the day may be asked to keep track of symptoms using a daily sleep journal. Many of the symptoms of narcolepsy can also be due to other sleep disorders, so a thorough workup and examination are important. However, cataplexy rarely occurs outside of narcolepsy. For someone who has symptoms that are concerning for narcolepsy, the next step towards a diagnosis is to undergo sleep tests with a medical provider at a sleep lab. Two types of sleep tests can help determine a diagnosis of narcolepsy.
In people for whom a sleep study is not an option, doctors can collect a sample of cerebrospinal fluid from the spinal canal to measure the amount of the brain hormone hypocretin-1. In people with narcolepsy Type 1, this hormone level is lower than normal.
Narcolepsy Treatments
While there’s no cure for narcolepsy, doctors have extensive treatment options available.
In addition to these steps, doctors will work with those who have narcolepsy to ensure they are engaging in activities as safely as possible. This may mean limiting driving to certain lengths of time or to specific times of the day. Reducing hazards at home may also be necessary.
If you suspect you have narcolepsy, see a doctor
There’s no cure for narcolepsy, but treatment may offer some insight and improvement in the quality of life. The key is to seek out help immediately to have a formal diagnosis completed.
Medically Reviewed
Sabina Hoque, MD MPH is a board-certified internal medicine physician with 10 years of clinical experience. In addition, she holds a masters in Public Health and has significant experience in teaching and biostatistics. She enjoys distilling complex medical information for audiences of varying levels of health literacy.
All content published on the HealthySleepGuide.com website is credited for informational purposes only. The information should not substitute as medical advice, diagnosis, or treatment. Always consult your doctor or qualified health professional with any questions regarding your health.