When you hear the word “narcolepsy,” you probably think of someone falling asleep without warning. And it’s easy to understand why: That’s how the condition is often depicted in movies and on TV.
It’s true that many people with narcolepsy fall asleep suddenly. But the disease’s hallmark symptom is actually excessive daytime sleepiness (EDS), which the National Heart, Lung, and Blood Institute describes as “an overwhelming sense of sleepiness” that comes on quickly. All patients who have narcolepsy experience EDS, though not all fall asleep without warning.
Along with EDS, there are more subtle signs of narcolepsy—symptoms that typically don’t make it into movies or TV shows, and vary from patient to patient. To understand these symptoms, it’s helpful to know that narcolepsy symptoms can differ between adults and kids and that the disorder comes in two types:
➡️ Type 1 narcolepsy is more common and is associated with low levels of a brain chemical called hypocretin, which helps regulates a person’s sleep-wake cycles, according to the National Institute of Neurological Disorders and Stroke (NINDS). Type 1 patients also experience sudden weakness or loss of muscle tone, which is known as cataplexy.
➡️ Type 2 narcolepsy patients, on the other hand, have normal brain levels of hypocretin and usually don’t experience cataplexy.
Think you or a loved one might have the condition? Here are seven subtle signs of narcolepsy to watch out for:
Weakness or muscle loss
Not only can cataplexy affect a narcolepsy patient’s whole body, but it can also cause weakness or muscle loss in specific body parts or regions. For example, some narcolepsy patients have problems speaking. Cataplexy can also make your head nod, or cause your hands to weaken so that you drop whatever you’re holding, according to the National Heart, Lung, and Blood Institute (NHLBI).
Some narcolepsy patients experience these bouts of muscle weakness just a few times a year, while others experience symptoms more often, per the Mayo Clinic.
If you have problems with your concentration or memory, or you feel like your thinking is muddled or “foggy,” these are all symptoms associated with narcolepsy, according to the NHLBI.
While each of these symptoms is not specific to narcolepsy—meaning they can stem from another condition (or simply from a lack of sleep)—they often make daily life a struggle for narcolepsy patients, finds a 2018 study in Medical Sciences.
Uncontrolled facial and body movements
In adults, narcolepsy is associated with sudden weakness or loss of muscle tone—often in response to laughter or strong emotion. Basically, a person’s body goes limp or loses strength.
But in kids, narcolepsy can cause some “active” movement patterns, rather than a loss of muscle tone. Raised eyebrows, grimacing, strange mouth and tongue movements, and body swaying—especially when a child is feeling strong emotion—are all symptoms of narcolepsy, according to a 2011 study in the journal Brain.
Have you ever been close to falling asleep—or on the verge of waking up—and found that, for a second or two, you can’t move your body? This is known as sleep paralysis, and many people who don’t have a sleep disorder experience it from time to time.
Sleep paralysis is also a symptom of narcolepsy, according to the Mayo Clinic. Some folks with narcolepsy experience this kind of paralysis all the time.
Having dreams immediately after falling asleep
Rapid eye movement (REM) sleep is a normal stage of a healthy sleep cycle—and the one in which you do most of your dreaming. Typically, REM sleep starts about 90 minutes after you fall asleep and repeats throughout the night, according to the NINDS.
But many narcolepsy patients transition into REM sleep quickly—within 15 minutes of falling asleep, according to the Mayo Clinic. If your brain’s dream factory seems to fire up the moment you fall asleep—and you know this because you often wake up from a dream very early after getting in bed and falling asleep—that could be a subtle indicator of narcolepsy.
Inability to sleep through the night
While narcolepsy is usually associated with daytime sleepiness, it can also cause problems when you’re in bed at night. Many narcolepsy patients experience fragmented sleep—meaning they struggle to sleep soundly throughout the evening, finds a 2015 study in the journal Chest.
Some narcolepsy patients wake up multiple times each night, and experts say this is caused by the same sleep-wake brain disturbances that cause narcolepsy patients to feel extremely tired during the daytime.
Vivid and frightening nightmares
Because narcolepsy can blur the boundaries between sleep and wakefulness, some patients experience very vivid and frightening dreams, according to the NHLBI.
For some patients, dreams can begin before a patient is fully asleep. An example is seeing or sensing an imaginary stranger in your bedroom while you’re still partially awake, says the Mayo Clinic.