When we think of sleep disorders, we often think of insomnia and the inability to fall or stay asleep. Yet, there are other sleep disorders that aren’t as widely understood. Narcolepsy is a sleep disorder characterised by extreme and uncontrollable daytime sleepiness.
Thanks in part to misrepresentations in popular culture and media, people often associate narcolepsy with visions of people falling asleep suddenly with no warning signs, collapsing into a heap. While it’s possible for people with narcolepsy to collapse suddenly, these are not the only symptoms—nor the most common.
In order to better understand narcolepsy and how it affects people living with the disorder, this article answers some key questions about the symptoms and causes of narcolepsy, as well as possible treatment options.
Narcolepsy is a rare neurological sleep disorder in which the brain is unable to effectively regulate the sleep-wake process. The primary symptom of narcolepsy is excessive daytime sleepiness (EDS). It can also cause other symptoms such as sleep paralysis and hallucinations. The symptoms of narcolepsy can impact a person’s ability to conduct daily activities, and cause increased risk of accidents and injuries.
When we sleep, we cycle through a range of sleep stages over the course of around 90 minutes. We go through both rapid and non-rapid eye movement stages, with rapid eye movement stage (REM) usually occurring towards the end of the cycle. In narcolepsy, the REM stage often begins much earlier in the cycle than normal.
Depending on whether a person experiences sudden physical collapse (cataplexy), they may be diagnosed with either narcolepsy type 1 (NT1) or type 2 (NT2).
NT1: A diagnosis of narcolepsy type 1 requires a person to either experience cataplexy or have low levels of the brain hormone hypocretin, which helps control wakefulness.
NT2: People with narcolepsy type 2 suffer similar symptoms to those with type 1, but do not experience cataplexy, and have normal levels of the brain hormone hypocretin. The symptoms tend to be less severe than in narcolepsy type 1.
The primary symptom of narcolepsy, whether type 1 or type 2, is excessive daytime sleepiness (EDS). Other symptoms can include cataplexy, sleep paralysis, hallucinations, and other sleep issues such as excessive physical movements and sleep apnea. Not everyone with narcolepsy experiences all of these symptoms. The major symptoms are explained below.
Regardless of how much sleep a person gets at night, people with narcolepsy experience excessive sleepiness and persistent and overwhelming urges to sleep during the day. Severe drowsiness can come on suddenly in what is referred to as a “sleep attack”. Everyone suffering from narcolepsy experiences EDS, and it is often the most obvious symptom.
Cataplexy is characterised by a sudden loss of muscle control, and it often occurs in response to strong emotions. Cataplexy can last from a few seconds to a few minutes. Occuring only in people with narcolepsy type 1, episodes of cataplexy can happen a few times throughout a person’s entire life, or many times throughout a single day. An episode could involve a minor loss of control of a small number of muscles, or it could affect the whole body, resulting in total collapse and an inability to speak or keep eyes open. People do not lose consciousness during cataplexy, however. While the loss of muscle control itself is not dangerous, a severe episode of cataplexy can result in injury if a person can’t find a safe place to fall.
Another possible symptom of narcolepsy is sleep paralysis, in which a person is unable to move while transitioning between sleep and wakefulness. Sleep paralysis typically lasts a few seconds or minutes. As with cataplexy, people recover their full ability to move immediately after an episode.
Visual, aural, or other sensory hallucinations can be another symptom of narcolepsy. Vivid and sometimes frightening or disturbing images can occur, usually at the edge of sleep when people are falling asleep or waking up.
Despite the excessive sleepiness that people with narcolepsy experience throughout the day, they often also experience difficulty staying asleep through the night. Disruptive sleep issues such as vivid dreaming, sleep apnea, and excessive movement are also more common in people with narcolepsy, further inhibiting full and restful sleep.
Automatic behaviours may occur when a person falls asleep during a familiar activity, such as eating, driving, or typing. The person temporarily loses consciousness of what they’re doing, continuing to perform the behaviour without awareness. Episodes of automatic behaviours can last a few seconds or a few minutes, and upon waking, the individual cannot recall their actions. A person may be talking to a friend, suddenly falling asleep but continuing to talk gibberish until they eventually wake again.
Even with ongoing studies helping to increase knowledge of the disorder, the precise causes of narcolepsy are not fully understood. Research suggests that a combination of factors could contribute to the presence of the disorder, yet most cases still occur with no clear cause. More is known about possible causes of narcolepsy type 1 than type 2.
Hypocretin is a naturally occurring brain hormone that helps to regulate the REM sleep stage and wakefulness. Since hypocretin levels are very low in almost all people who experience episodes of cataplexy, it can help to consider possible causes of low hypocretin. Auto-immune disorders, genetics and family history, and brain injuries are all factors that can result in very yellow hypocretin in the brain.
People with a family history of narcolepsy type 1 are 1-2% more likely to have the condition.
Type 1 can also occur because of a separate medical condition, such as an infection or injury, that causes damage to the hypocretin-producing parts of the brain containing hypocretin-producing neurons.
Treatment of narcolepsy is focused on reducing symptoms and their impact on the patient’s safety and quality of life. There is no cure for the disorder, though it’s often possible to manage symptoms through a combination of behavioural approaches and medication. All treatment plans should be tailored by a doctor, who can guide patient’s through treatments to suit their unique situation.
Although there is no cure for narcolepsy, some of the symptoms can be treated with medicines and lifestyle changes. When cataplexy is present, the loss of hypocretin is believed to be irreversible and lifelong. Excessive daytime sleepiness and cataplexy can be controlled in most individuals with medications.
Behavioural approaches to treatment include habits, actions and routines that people with narcolepsy can incorporate into their daily lives, building healthy strategies that reduce the impact of symptoms on a person’s physical and mental health.
Schedule naps: Short naps are refreshing for people with narcolepsy, so scheduling daytime naps ahead of time can reduce EDS. Naps can be planned around times when people tend to feel sleepy.
Take time to unwind and relax before bed: Relaxing with a book, journaling, or taking a warm bath before bed can help to promote sleepiness in the evening.
Make healthy food choices: Eating a healthy, nutrient-rich diet and avoiding heavy meals before bedtime can help to improve overall health for people with narcolepsy.
Exercise: Daily movement improves sleep quality and can help prevent weight gain. People with narcolepsy can choose a safe exercise to incorporate into their daily activities.
Sleep hygiene: Keeping a regular sleep schedule, creating a sleep environment where light, noise, and other distractions can be minimised, and limiting screen time before bed can help to improve sleep at night.
Avoid alcohol: Alcohol can increase drowsiness, which contributes to EDS and other daytime symptoms.
Avoid caffeine and cigarettes, especially before bedtime.
Build a support network: Working with a counsellor, sleep coach, or support group can help relieve some of the psychological and emotional strain people with narcolepsy may experience as a symptom of poor sleep, and build coping strategies for the lifestyle and social stressors associated with managing the disorder.
While behavioural approaches are often helpful, most people diagnosed with narcolepsy also receive medical treatment, using prescription medication that help to manage or improve one or more symptoms.
Some of the medications used to treat narcolepsy include modafinil, amphetamine stimulants such as methylphenidate, sedatives such as sodium oxybate, and some kinds of antidepressants.
These medications can have significant side effects. People with narcolepsy should talk to their doctor about all of the possible benefits and risks, working together to determine the best medication and behavioural treatments to help them manage the disorder and their symptoms.