What Is Cataplexy? Symptoms, Causes, Diagnosis, Treatment, and Prevention

Cataplexy is a brain disorder that causes a sudden and temporary loss of muscle tone and control, according to the National Institute of Neurological Disorders and Stroke (NINDS).

The episodes (or “cataplectic attacks”) in most cases are triggered by strong or extreme emotions, including anger, stress, anxiety, fear, a depressed mood, joy, and laughter.

The vast majority of people who experience cataplexy do so as a result of having type 1 narcolepsy, a chronic sleep and neurological disorder in which the brain has trouble properly controlling wake and sleep cycles.

In very rare cases, cataplexy has been reported in individuals without narcolepsy, notes past research.

Living with cataplexy is challenging. You cannot always control your emotions or emotional response, so cataplectic attacks can occur randomly. For some, it means being constantly vigilant about how to avoid losing control of their bodies, notes Mayo Clinic.

Here are some important things to know about why cataplexy happens, its connection to narcolepsy, and how to manage the potentially debilitating symptom.

Signs and Symptoms of Cataplexy

Cataplexy — episodes of uncontrollable muscle weakness — typically last a few seconds to a few minutes, and can happen as infrequently as a few times a year or as often as a few times a day, according to MedlinePlus.

They are typically caused by a strong feeling of sadness, excitement, joy, or other emotion, and can cause someone's knees to buckle, their head to bob, or cause them to fall down if they are standing and lose control of their leg muscles, explains Shelley Hershner, MD, associate professor of neurology and director of the Collegiate Sleep Clinic at the University of Michigan in Ann Arbor, who has worked on the narcolepsy quality metrics for the American Academy of Sleep Medicine.

Cataplexy is often misdiagnosed as a seizure disorder; but unlike fainting or seizure disorders, people who experience cataplexy are awake and aware of what's happening — though some may fall asleep after the episode ends, notes the Sleep Foundation.

People who have cataplexy must constantly be on guard to avoid injury. When an episode of cataplexy strikes, an individual may slump, lose his or her grip on something, or fall down.

“Some people may avoid swimming, climbing a ladder, or taking a bath,” says Dr. Hershner.

Cataplexy can cause muscle weakness in any part of the body, though cataplexy commonly affects the limbs (hands may drop whatever they're holding, knees may buckle, legs may collapse) and face (eyelids may droop, the jaw may go slack and speech become slurred, the head may nod). The attacks can range from mild, such as a slight drooping of the eyelids, to severe, such as a total body collapse, according to the Merck Manual.

Causes and Risk Factors of Cataplexy

The vast majority of cases of cataplexy occur because an individual has type 1 narcolepsy.

The exact cause of narcolepsy is unknown, but people with type 1 narcolepsy have abnormally low levels of a sleep-wake regulating brain hormone called hypocretin (also known as orexin), notes the National Organization for Rare Disorders.

This deficiency can cause rapid eye movement (REM) sleep to happen at the wrong time, according to Harvard Medical School.

It’s not clear what causes this loss of hypocretin, but it may be the result of immune system changes that cause the immune system to attack hypocretin-containing brain cells.

Most people who are diagnosed with narcolepsy do have cataplexy, too.

In some cases, type 2 narcolepsy — the one without cataplexy, which has milder symptoms — may develop into narcolepsy with cataplexy, says Eric Olson, MD, a professor of medicine and sleep medicine specialist at the Mayo Clinic in Rochester, Minnesota, and a board member of the American Academy of Sleep Medicine.

Understanding REM sleep — specifically, the way that sleep cycles are disrupted in people with narcolepsy — may help us gain insight into why cataplexy happens in people with narcolepsy. In normal sleep cycles, people go through three stages of non–rapid eye movement (NREM) sleep before entering the REM phase, according to Harvard Medical School.

It takes roughly 70 to 100 minutes to go through the first NREM-REM cycle of the night, and 90 to 120 minutes during later cycles, which continue to repeat throughout the night.

But these cycles malfunction in people with narcolepsy. They may enter REM sleep right away when they fall asleep, and then wake up, bypassing the NREM stage; this can occur both during the night as well as during daytime naps, blurring the lines between wakefulness and sleep.

RELATED: What's Happening in the Brain During the Stages of Sleep

Another important point: The REM stage of sleep is when dreaming occurs, and when our bodies become paralyzed — a mechanism that is thought to prevents us from acting out our dreams and harming ourselves, according to the Sleep Foundation.

In people with narcolepsy, this sleep paralysis associated with REM sleep happens at the wrong time, too, which is why sleep paralysis and vivid hallucinations while falling asleep or waking up can also occur.

Cataplexy episodes resemble that loss of muscle control that naturally happens during REM sleep — but occur when someone is awake rather than during sleep.

Research published in the Journal of Neuroscience suggested that in healthy individuals, positive emotions may lead to muscle weakness (feeling weak with laughter, for instance), but that the brain chemical hypocretin (the one absent in people with narcolepsy) prevents that loss of muscle tone from being anything more than a brief event.

This may help explain why, in people who have narcolepsy with cataplexy, that response is more extreme. More research needs to be done to better understand why and how strong emotions trigger this response to begin with, as well as the role of hypocretin in narcolepsy symptoms and treatment.

How Is Cataplexy Diagnosed?

Most people with cataplexy have type 1 narcolepsy, and cataplexy is the first symptom to appear in about 10 percent of narcolepsy cases. However, cataplexy can be misdiagnosed as a seizure disorder.

If you feel the sudden urge to sleep during the day even after a night of good sleep, doze off at inappropriate times (when working or talking to a friend), have dream-like hallucinations just before falling asleep, or experience momentary paralysis while awake, you may have narcolepsy with cataplexy, according to Harvard School of Medicine.

However, most primary care physicians don't know how to recognize and treat narcolepsy, so you may want to see a sleep doctor if you suspect you have this condition.

Or, your primary care doctor can refer you to a sleep specialist.

To determine if you have narcolepsy with cataplexy, your sleep doctor may first ask you for a detailed sleep history, which often includes filling out a short series of questions to gauge your sleepiness, formally known as the Epworth Sleepiness Scale. You may be asked to keep a detailed sleep log for one or two weeks, and to wear a wristwatch-like device known as an actigraph to measure periods of activity and rest.

If your sleep history, sleep diary, and actigraph data suggest you may have narcolepsy, your doctor will have you spend the night at a sleep center to undergo a series of tests. These tests can help determine the severity of your narcolepsy, or identify other possible causes for your symptoms.

Per the American Academy of Sleep Medicine, tests may include the following:

Polysomnography Using electrodes attached to your scalp, this test measures the electrical activity of your brain and heart, and the movement of your muscles and eyes during sleep. This test requires an overnight stay at a medical facility.
Multiple Sleep Latency Test Also known as a daytime nap study, this full-day test evaluates excessive daytime sleepiness by measuring how quickly you fall asleep during the day. It is the standard tool used to diagnose narcolepsy.
Hypocretin Level Measurement This test measures your hypocretin levels. People with low or no hypocretin are classified as having type 1 narcolepsy. However, because this test requires your physician to remove cerebrospinal fluid (a fluid that protects your brain and spinal cord) from your lumbar spine, it is rarely used.

Treatment and Medication Options for Cataplexy

There is no cure for cataplexy or narcolepsy.

Symptoms of narcolepsy (including cataplexy) typically develop over several months and last a lifetime.

Depending on the severity, some people with cataplexy may only have one or two attacks in a lifetime, whereas others may experience multiple attacks a day.

Without proper diagnosis and treatment of narcolepsy, symptoms such as cataplexy can be dangerous and “life-restricting,” notes Dr. Olson. “Someone may stop competing to avoid winning something, or avoid laughing, or even engaging in intercourse,” says Olson.

Who Should Be on Your Narcolepsy Healthcare Team?

In short, people affected by cataplexy may learn to modify their behavior and activities to minimize their risk of bringing on an episode, and many end up avoiding situations that may cause cataplexy.

These adjustments can be consequential and vastly affect quality of life, such as if someone skips social situations with friends, or avoids driving, according to Harvard Medical School.

However, while narcolepsy with cataplexy is a lifelong condition, there are medications that can help you manage the symptoms.

Medication Options for Cataplexy

There are drugs that have been shown to be effective in treating cataplexy. Medications may reduce cataplectic attacks by 90 percent, or eliminate them entirely in some people, notes Harvard Medical School.

The primary treatment options are medications that allow people to stay awake during the day, and push them to sleep at night, says Lois E. Krahn, MD, a professor of psychiatry in the Mayo Clinic College of Medicine in Phoenix, Arizona, and a sleep medicine researcher with a special focus on narcolepsy.

There is some evidence that tricyclic antidepressants, such as clomipramine, imipramine, and desipramine, and selective serotonin reuptake inhibitors (SSRIs) may be helpful for cataplexy, as well as other narcolepsy symptoms.

Sodium oxybate, taken at night for its sedative effect, has also been shown to be effective in treating severe daytime sleepiness as well as cataplexy attacks.

If an individual has very rare episodes of cataplexy, intervention may be unnecessary.

But people who experience frequent attacks (or ones that greatly disturb their lives) should discuss medication options with their doctor and consider the potential benefits, as well as possible side effects. For people with severe cataplexy, being able to take medication that can help control attacks may significantly improve social interaction, safety, and overall quality of life.

Alternative and Complementary Therapies for Cataplexy

In addition to medications, cognitive behavioral therapy (CBT), or learning techniques to improve behavior, may help people manage several symptoms of narcolepsy, including cataplexy, per past research.

CBT techniques for narcolepsy vary, but can involve helping patients recognize conditions and emotions that trigger their cataplectic attacks, and teaching them how to respond in ways that prevent an attack from occurring. Another potential CBT technique is known as stimulus satiation, a procedure in which the patient is repeatedly exposed to the trigger that prompts cataplectic episodes until its effect is lost. However, most studies have looked at CBT for other sleep disorders, and more research on the application of CBT for narcolepsy is needed.

Counseling and support groups can also help people with narcolepsy learn coping strategies to help manage symptoms like cataplexy.

Find a support group through Narcolepsy Network. Or ask your doctor to help you locate a support group or qualified counselor.

Prevention of Cataplexy

Medications are typically the most effective way to prevent cataplexy, though other strategies may also help, according to Harvard Medical School:

Get enough sleep or plan strategic naps. You may be more likely to experience a cataplectic attack when you're sleep-deprived. “If someone is exhausted, they are more vulnerable to an emotional trigger, so being well-rested is important,” Dr. Krahn says. If you're unable to get a good night's sleep, or you're bothered by excessive daytime sleepiness, try to take short, scheduled naps at times when you tend to feel sleepiest. “Naps don't have to be terribly long — a person with narcolepsy can benefit from a 20-minute nap,” Krahn says.
Get up and move. Regular physical activity may indirectly help with cataplexy by keeping daytime sleepiness at bay, according to Krahn. So, if you start feeling sleepy, and you can't take a quick nap, go for a walk.
Get help from friends, family, and coworkers. Let people know if your cataplexy is triggered by strong emotions or specific situations. If you sense an attack is coming, encourage people to avoid these triggers if possible. Though you may not want to avoid strong emotions or specific situations, it may be preferable to an attack — especially if an attack is about to occur at an awkward time (like during a meal or work meeting).

Complications of Cataplexy

One of the more common complications of cataplexy is physical harm.

Cataplexy can cause injury to yourself or others if it occurs while you're driving, cooking, or operating machinery.

Severe attacks can also cause head trauma, such as bleeding between the brain tissue and skull (also known as an intracranial hemorrhage), according to Stat Pearls.

Cataplexy can also interfere with relationships and daily life. As many attacks are triggered by intense emotions, like anger and joy, people with cataplexy may withdraw from emotional interactions, or avoid social situations.

Research and Statistics: How Common Is Cataplexy?

Roughly 70 million Americans suffer from sleep disorders like insomnia, sleep apnea, restless legs syndrome, and narcolepsy, according to the Cleveland Clinic.

Narcolepsy occurs in men and women equally and is estimated to affect roughly 1 in 2,000 people in the United States, which equals roughly 200,000 Americans and 3 million people worldwide, notes the Narcolepsy Network.

Roughly half of all people with narcolepsy also have cataplexy, per Harvard Medical School.

However, because narcolepsy is often unrecognized or misdiagnosed, the actual number may be higher.

The symptoms of narcolepsy (including cataplexy) can appear at any age, but they typically start in childhood, adolescence, or young adulthood (ages 7 to 25).

Symptoms will develop over the course of several months and last a lifetime.

Conditions Related to Cataplexy

The following conditions can cause and be associated with cataplexy:

Narcolepsy This is a chronic neurological disorder that affects the brain’s sleep-wake cycles.
Excessive Daytime Sleepiness (EDS) One of the most obvious symptoms of narcolepsy is excessive daytime sleepiness, or the overwhelming need to sleep, regardless of how much sleep you may have gotten the night before. Some people are more likely to experience a cataplectic attack when sleepy.
Sleep Paralysis This common narcolepsy symptom resembles cataplexy, except it occurs during sleep.

Resources We Love

American Academy of Sleep Medicine (AASM)

Founded in 1975, this professional society now has a combined 11,000 accredited member sleep centers, physicians, scientists, and other sleep-focused healthcare professionals. The society offers professional development opportunities for physicians, as well as a variety of sleep resources for the general public, including a sleep education site with a directory of sleep centers, patient-friendly guides that explain clinical practice guidelines, and a monthly research journal.

National Sleep Foundation (NSF)

This nonprofit has been an advocate for sleep and health for nearly 30 years. Their site provides helpful articles about a variety of sleep topics and their content is reviewed by a medical team to ensure the information is accurate and up-to-date.

Mayo Clinic

The Mayo Clinic offers everything you need to know about narcolepsy with cataplexy: what it is, symptoms and causes, and when to see a doctor for help. This well-known hospital also provides detailed information about the tests used to diagnose narcolepsy, medications to treat narcolepsy, how to prepare for your appointment with your doctor, and what questions you can expect from your doctor during your initial visit.

National Institute of Neurological Disorders and Stroke (NINDS)

This division of the National Institutes of Health focuses on researching the brain and nervous system to reduce neurological disorders and diseases (like narcolepsy with cataplexy). Their site offers a detailed fact sheet about narcolepsy, including the latest research and clinical trials. You'll also find a list of recommended resources for finding more information about narcolepsy.

Narcolepsy Network

Founded in 1986, this nonprofit provides education and resources to support people with narcolepsy. Find support groups (including advice for starting your own), informational videos, directories to find a sleep specialist or center, and a listing of additional sites where you can find more resources.

Wake Up Narcolepsy (WUP)

WUP is a nonprofit dedicated to raising awareness about narcolepsy, as well as supporting research to find a cure. Join their online support group, attend an event, tune in to their weekly podcast, or browse their informational videos and brochures.

Harvard Medical School Division of Sleep Medicine

Harvard Medical School offers a comprehensive site dedicated to understanding, treating, and living with narcolepsy. You’ll find helpful resources for managing narcolepsy day-to-day, including a video series featuring real-life patients and educators. Still not sure if you have narcolepsy? The site offers self-evaluation tools, as well as tips for finding a qualified sleep medicine specialist.

Additional reporting by Katherine Lee.