Excessive Daytime Sleepiness: Causes, Symptoms and Treatments

We’ve all had those days when it’s a struggle to stay awake. You might even nod off in a meeting, class, or a movie. As long as you keep moving, you’re okay, but the moment you sit down, the temptation to crawl under your desk and take a nap is all too real.

Most of the time, a good night’s sleep is enough to set things right. However, for some people, those days drag on into weeks or even months. This chronic sleepiness is called excessive daytime sleepiness, EDS for short. For those who experience it, EDS is much more than an inconvenience; it’s a sign of something much more serious.

To understand why EDS occurs and what to do about it, we’ve dug into its causes, symptoms, and treatments in this article.

What is Excessive Daytime Sleepiness?

People with Excessive Daytime SleepinessVerified Source National Library of Medicine (NIH)World’s largest medical library, making biomedical data and information more accessible.View source find it difficult to stay awake or alert during regular waking hours. EDS is considered and often referred to as a hypersomnia, a term that also includes sleeping too much at night and prolonged sleep inertia.

While we all periodically experience an overwhelming urge to sleep during the day, this sleepiness becomes “excessive” when it becomes a near-daily occurrence for three months or more.

EDS affects a large percentage of the population, an estimated 10 to 20 percentVerified Source National Library of Medicine (NIH)World’s largest medical library, making biomedical data and information more accessible.View source of the population. At the high end, that’s more than 65 million Americans at the time of this writing, and the number number may be increasingVerified Source National Library of Medicine (NIH)World’s largest medical library, making biomedical data and information more accessible.View source. A 2020 poll by the National Sleep Foundation found that about half of adults feel sleepy three to seven days a week. The average for women was 3.4 days a week; for men, it was a little lower at 2.7.

According to the report, this sleepiness doesn’t just affect an individual’s ability to stay awake. It often interferes with their everyday life, negatively impacting their productivity, mood, and overall well-being.

The Difference Between Sleepiness and Fatigue

While the words sleepiness and fatigueVerified Source National Library of Medicine (NIH)World’s largest medical library, making biomedical data and information more accessible.View source are often used synonymously and both involve an experience of low energy, there is an essential difference between the two.

People with fatigue are tired but not necessarily sleepy. It may take them some time to fall asleep, despite the exhaustion they feel. People with sleepiness issues, in contrast, have trouble with an increased drive to fall asleep.

Symptoms of EDS

Drowsiness is, obviously, the most common symptom of EDS. However, there are other indications of sleepinessVerified Source National Library of Medicine (NIH)World’s largest medical library, making biomedical data and information more accessible.View source that aren’t as clear. These include the following:

• Irritability or moodiness
• Difficulty staying alert
• Struggles with concentration and focus
• Memory issues
• Inability to retain new concepts/information
• Brain fog and difficulty making decisions
• Slow reaction times

If these symptoms seem familiar, it’s for a good reason: sleep deprivation and EDSVerified Source National Library of Medicine (NIH)World’s largest medical library, making biomedical data and information more accessible.View source often go hand-in-hand, resulting in similar signs and consequences.

Excessive Sleepiness Causes and Related Conditions

It’s crucial to note that EDS is not a disorder in and of itself but an indication thatVerified Source National Library of Medicine (NIH)World’s largest medical library, making biomedical data and information more accessible.View source something else is at play.

EDS can be caused by a lack of quality sleep caused by poor sleep habits, an underlying sleep condition, or even another medical condition. Some of these issues are minor and easily treatable through simple lifestyle changes. Others are severe and require medical intervention to manage.

Lack of Sleep

Persistent lack of sleep is one of the most common and treatable causes of EDS. The Centers for Disease Control and Prevention recommends around seven to eight hoursVerified Source Centers for Disease Control and Prevention (CDC)The United States’ health protection agency that defends against dangers to health and safety.View source of sleep for adults each night. Unfortunately, many of us fall short of the minimum sleep durationVerified Source Centers for Disease Control and Prevention (CDC)The United States’ health protection agency that defends against dangers to health and safety.View source on a regular basis.

Sleep deprivation is often due to long working hours, shift work, an irregular schedule, or insomnia. Sometimes it’s because we just don’t value sleep as much as we should.

Not getting enough sleep isn’t just a problem for adults either. Today’s kids get less sleep on average than previous generations, but not because they don't need itVerified Source Centers for Disease Control and Prevention (CDC)The United States’ health protection agency that defends against dangers to health and safety.View source.

Poor Quality Sleep

Fragmented or poor quality sleep is another frequent cause of EDS. When our sleep is shallow or broken, the body doesn’t get the full value of deep sleep. Getting up throughout the night, too much time on electronic devices, and not getting enough exercise are often to blame for poor sleep. Many sleep conditions negatively impact the quality or quantity of our sleep as well.

SEE ALSO: Time Management and Sleep

Sleep Conditions

Excessive Daytime Sleepiness is a symptom of many sleep conditions, including sleep apnea and circadian rhythm disorders.

Sleep Apnea & Hypopnea

Sleep apnea and hypopnea are breathing disorders that cause people to stop or experience shallow breathing during sleep. Because the body wakes itself up to restart normal breathing, sleep becomes fragmented.

What causes these breathing difficulties can vary. Obstructive sleep apneaVerified Source National Library of Medicine (NIH)World’s largest medical library, making biomedical data and information more accessible.View source and hypopnea occur when the airways are blocked, while central sleep apnea and hypopnea are considered “central,” meaning that they are caused by a disconnect between the brain and body.

Sleep apnea and hypopnea symptoms include loud snoring (obstructive only), waking up choking or gasping for air, and this can lead to many of the typical sleep deprivation symptoms including moodiness, irritability, and difficulty concentrating during the day.

Sleep apnea is diagnosed with a sleep study. Typical treatments include lifestyle changes like weight loss and improved sleep hygiene, surgery, and CPAP machines or other devices to keep air moving through the airways.

SEE ALSO: What Is CPAP?

Insomnia

The inability to fall asleep, even when tired, is called insomniaVerified Source National Library of Medicine (NIH)World’s largest medical library, making biomedical data and information more accessible.View source. It may also manifest as waking up frequently throughout the night or waking up very early and being unable to return to sleep.

Most people experience insomnia at some point in their lives, but few experience long-term issues. However, for nearly 10% of the population, insomnia is chronic, with at least three episodes per week for three months or more.

Insomnia is frequently associated with poor sleep habits, stress, mental health disorders, some neurological issues, and the use of certain medications. In addition to daytime sleepiness, symptoms include anxiety and depression, worry over sleep, lack of coordination, headaches, and difficulty concentrating.

While the experience of insomnia is easily identified, it can be more challenging to determine the root cause. A doctor will usually perform a thorough exam, ask questions, and even request that you keep a sleep diaryVerified Source National Library of Medicine (NIH)World’s largest medical library, making biomedical data and information more accessible.View source or undergo a sleep study.

Remedies for chronic insomnia include:

• Managing stressVerified Source National Library of Medicine (NIH)World’s largest medical library, making biomedical data and information more accessible.View source
• Getting sunlightVerified Source National Library of Medicine (NIH)World’s largest medical library, making biomedical data and information more accessible.View source to maintain an appropriate sleep-wake cycle
• Engaging in cognitive behavioral therapy for insomniaVerified Source National Library of Medicine (NIH)World’s largest medical library, making biomedical data and information more accessible.View source (CBT-I).

SEE ALSO: Best Mattresses for Insomnia

Restless Leg Syndrome

Another central disorder, restless legs syndromeVerified Source National Library of Medicine (NIH)World’s largest medical library, making biomedical data and information more accessible.View source (RLS) is defined by an uncontrollable urge to move the legs when they’re at rest. People with RLS may also experience uncomfortable sensations in the legs, like tingling or burning.

About 10% of the population experiences some symptoms of RLS. While the reasons for the condition are not fully understood, there may be some connections between family history and neurological disorders. Many pregnant women develop RLS, and it is also associated with iron deficiency and chronic renal failure.

RLS symptoms can occur while sleeping or awake and may make it difficult to fall asleep. Spasms in the legs while asleep often hinder restful sleep, frequently waking the person up or simply preventing deep sleep. This poor sleep results in excessive sleepiness during the day.

Treatment for RLS includes improving sleep habits and addressing iron and kidney issues. Exercise often helps, as do massage and soothing baths.

Narcolepsy

Narcolepsy is a central condition that affects the REM cycleVerified Source National Library of Medicine (NIH)World’s largest medical library, making biomedical data and information more accessible.View source and causes a person to fall asleep during the day, even in the middle of doing something active. This lack of control over one’s wakefulness makes narcolepsyVerified Source National Library of Medicine (NIH)World’s largest medical library, making biomedical data and information more accessible.View source an exceptionally challenging and even dangerous condition. Thankfully, narcolepsy is relatively rare.

People with narcolepsy often experience sleep paralysis and hallucinations while falling asleep or waking up. They may also have bouts of cataplexy, a sudden loss of strength that causes the person to collapse. Strong emotions often trigger cataplexy.

Chemical and hormonal imbalances, brain injuries, and infections have been tied to narcolepsy. In addition to traditional sleep studies, a diagnosis of the condition often involves a multiple sleep latency testVerified Source National Library of Medicine (NIH)World’s largest medical library, making biomedical data and information more accessible.View source. This daytime study measures how quickly you fall asleep and enter REM sleep while napping.

SEE ALSO: The History of Sleep Paralysis

Circadian Rhythm Disorders

The circadian rhythm is the body’s natural daily clock, which manages processes like sleep and hunger throughout a 24 hour period. Circadian rhythm sleep disorders occur when there is a disconnect between the body clock and our sleep-wake cycle. These include:

• Delayed sleep phase syndrome, where bedtime is very delayed
• Advanced sleep phase syndrome, where bedtime is unusually early
• Irregular sleep-wake syndrome, with no discernible pattern to the body’s daily sleep-wake cycle
• Non-24 hour sleep-wake disorder, where the body is on a schedule longer than 24 hours

Other disruptions to the circadian rhythm include shift work sleep disorder and jet lag, both of which cause irregular sleep-wake patterns.

Regardless, any disconnect between life and sleep schedules disrupts sleep. Many people with circadian rhythm disorders can experience insomnia and excessive daytime sleepiness.

Basic lifestyle changes can help to get your sleep cycle back on track. These include getting sunlight early in the day, limiting exposure to light late in the evening, avoiding caffeine, avoiding or limiting naps, and sticking to a regular sleep schedule.

SEE ALSO: 8 Reasons to Get the TV Out of Your Bedroom

Non-Sleep Medical Conditions

While sleep issues are the most apparent cause of daytime sleepiness, other chronic medical conditions and mental health disorders have been associated with EDS. These conditions may accompany or cause sleep disorders or cause general drowsiness on their own:

• Mental health disorders, such as depression, anxiety, and PTSD
• Neurodegenerative diseases like dementiaVerified Source National Library of Medicine (NIH)World’s largest medical library, making biomedical data and information more accessible.View source and Parkinson’s diseaseVerified Source National Library of Medicine (NIH)World’s largest medical library, making biomedical data and information more accessible.View source
• Obesity, which is often a significant risk factor for obstructive sleep apnea and hypopnea, as well as other conditions
• Neurological issues such as attention deficit hyperactivity disorderVerified Source National Library of Medicine (NIH)World’s largest medical library, making biomedical data and information more accessible.View source and autism spectrum disordersVerified Source Medline PlusOnline resource offered by the National Library of Medicine and part of the National Institutes of Health.View source
• Metabolic issues, including diabetesVerified Source National Library of Medicine (NIH)World’s largest medical library, making biomedical data and information more accessible.View source and hypothyroidismVerified Source National Library of Medicine (NIH)World’s largest medical library, making biomedical data and information more accessible.View source
• Long-term severe illnesses, such as chronic pain, cardiovascular disease, and cancerVerified Source National Library of Medicine (NIH)World’s largest medical library, making biomedical data and information more accessible.View source

In addition, certain medicationsVerified Source Harvard HealthBlog run by Harvard Medical School offering in-depth guides to better health and articles on medical breakthroughs.View source used to treat these and other conditions may also contribute to poor sleep or daytime drowsiness. These include antidepressants, antihistamines, antipsychotics, and blood pressure medications, among others.

Idiopathic Hypersomnia

Unlike the sleep conditions noted above, idiopathic hypersomniaVerified Source National Library of Medicine (NIH)World’s largest medical library, making biomedical data and information more accessible.View source (IH) is a condition defined explicitly by excessive daytime sleepiness. The cause for this hypersomnia is unknown, but it is a neurological condition related to the brain and its functioning.

Symptoms of idiopathic hypersomnia include waking up not feeling rested, taking long naps that only make you feel worse, and brain fog or the inability to focus. People with IH also often experience prolonged sleep inertia, which is also known as “sleep drunkenness.” Sleep inertia is the feeling of being groggy or confused upon waking.

IH is not common, and it is diagnosed by ruling out other potential sleep disorders. Treatment often involves medication.

Consequences of Excessive Sleepiness

Left untreated, all of this sleepiness can add up to some significant consequences. EDS has been shown to reduce overall quality of life, with sleepiness linked to:

• Reduced productivity at work or school
• An increased risk of errors and accidentsVerified Source National Library of Medicine (NIH)World’s largest medical library, making biomedical data and information more accessible.View source
• Social and relationship problems

In addition, sleep conditions are linked to higher incidences of health issues, including:

• Heart diseaseVerified Source Oxford AcademicResearch journal published by Oxford University.View source
• Poor development in kidsVerified Source National Library of Medicine (NIH)World’s largest medical library, making biomedical data and information more accessible.View source
• Increased risk for fallsVerified Source National Library of Medicine (NIH)World’s largest medical library, making biomedical data and information more accessible.View source
• Cognitive impairmentVerified Source ScienceDirectOne of the largest hubs for research studies and has published over 12 million different trusted resources.View source
• Earlier mortalityVerified Source National Library of Medicine (NIH)World’s largest medical library, making biomedical data and information more accessible.View source

It’s clear that addressing daytime sleepiness issues is essential to overall health and enjoyment of life.

Should You Be Concerned About Daytime Sleepiness?

If you’re sleepy every once in a while, but it’s not causing you problems, there’s probably nothing to worry about. However, if sleepiness is consistently affecting your life, a doctor may be able to help you understand and address persistent issues.

You should see a doctor when you experience any of the following long-term symptoms:

• Your sleepiness is nearly constant
• You can’t shake the brain fog
• You’re struggling with short-term memory and other cognitive issues
• You are concerned about falling asleep while driving or doing other high-risk activities
• You can’t sleep at night, despite being exhausted
• You’re snoring loudly or showing other symptoms of disordered sleep

As noted above, different conditions require various tools and methods to diagnose them. However, doctors will usually run tests and ask questions about your sleep habits and general health. In some cases, a sleep studyVerified Source Medline PlusOnline resource offered by the National Library of Medicine and part of the National Institutes of Health.View source, also known as polysomnographyVerified Source Medline PlusOnline resource offered by the National Library of Medicine and part of the National Institutes of Health.View source, can help identify specific sleep conditions.

For daytime sleepiness, a multiple sleep latency testVerified Source National Library of Medicine (NIH)World’s largest medical library, making biomedical data and information more accessible.View source is standard. During the test, patients take four or five naps, each two hours apart. The study measures the rate at which you fall asleep, and the average across the naps indicates your sleepiness level.

Treating Excessive Sleepiness

When hypersomnia is caused by a sleep condition or other medical concern, addressing those problems will often resolve or improve it.

Making changes to your lifestyle can help improve your nighttime slumber and your daytime awakeness across the board. These include:

• Eating a healthy dietVerified Source Oxford AcademicResearch journal published by Oxford University.View source
• Limiting caffeine
• Exercising regularly for good sleep
• Improving general sleep hygiene

Spending time outdoors, especially in the morning, is another critical element to help address daytime sleepiness. Our circadian rhythms are naturally tied to daylight, and so exposing ourselves to natural light at the right times is key to regulating our circadian rhythms.

When these methods aren’t enough and more aggressive treatment is needed, other options include using stimulants to stay awake during the day or other medications to help bolster your energy. Your doctor can help you determine the treatment plan that is right for you.

SEE ALSO: 7 Tips for Better Sleep

Frequently Asked Questions

What causes excessive sleepiness?

Several medical conditions, psychiatric conditions, and sleep disorders can be behind a case of excessive daytime sleepiness. Excessive sleepiness can also be the result of medication with sedatory side effects. Because it’s difficult to nail down one cause without testing, it’s best to share any concerns with your doctor.

Is excessive sleepiness a disorder?

Excessive sleepiness is usually treated as a symptom of an underlying condition rather than a disorder in and of itself. This means it’s usually not treated on its own, and instead a specialist must investigate to determine the cause behind it.

If you regularly experience sleepiness and it keeps you from living a full life, it’s best to speak with your doctor about possible reasons you aren’t feeling rested.

Which medical conditions cause excessive daytime sleepiness?

Conditions that can cause excessive sleepiness include depression, restless leg syndrome, narcolepsy, insomnia, depression, and obstructive sleep apnea. Because of the wide range of potential conditions that can lead to excessive sleepiness, it’s best to speak with a specialist to rule out different causes.

Once a diagnosis has been achieved, it will be easier to devise a treatment plan.

Is oversleeping a symptom of depression?

Oversleeping can be a symptom of depression. However, an inability to sleep can also be a side effect of depression. A sleep disorder by itself does not cause depression, but it can exacerbate the effects of depression.

Depression isn’t the only mental condition associated with oversleeping. Sleeping too much can also be linked to another mental illness, such as general anxiety disorder and post traumatic stress disorder.

Is excessive sleepiness a sign of narcolepsy?

Excessive daytime sleepiness is one of the more prominent signs of narcolepsy. However, while excessive daytime sleepiness is usually the first symptom that narcolepsy patients notice, having excessive sleepiness doesn’t necessarily mean you’re narcoleptic. Excessive daytime sleepiness is also a symptom of obstructive sleep apnea, insomnia, and other sleep disorders.

It is important to see a sleep specialist who can run a series of tests to determine a proper diagnosis.

Final Thoughts on Excessive Daytime Sleepiness

It’s normal to be sleepy after a night of poor sleep, and everyone experiences it once in a while. But when that sleepiness is severe and persistent, an underlying problem is often to blame.

Sometimes excessive sleepiness is resolved simply by improving one’s sleep habits. Other times, professional intervention is required. In either case, addressing sleep issues is key to a good quality of life.