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Insomnia and Excessive Daytime Sleepiness (EDS)


Richard J. Schwab

, MD, University of Pennsylvania, Division of Sleep Medicine

Last full review/revision Jun 2020| Content last modified Jun 2020

The most commonly reported sleep-related problems are insomnia and excessive daytime sleepiness.

  • Insomnia is difficulty falling asleep or staying asleep, waking up early, or a disturbance in sleep quality that makes sleep seem inadequate or unrefreshing.
  • Excessive daytime sleepiness refers to being unusually sleepy or falling asleep during the day.

(See also Overview of Sleep.)

Difficulty falling and staying asleep and waking up earlier than desired are common among young and old. About 10% of adults have long-standing (chronic) insomnia, and about 30 to 50% sometimes have insomnia.

Did You Know...

  • Almost half of people have insomnia at one time or another.
  • Prescription sleep aids and over-the-counter sleep aids that contain diphenhydramine are not good choices for treating insomnia.
  • The best treatment for insomnia is cognitive-behavioral therapy, which includes changes in behavior to improve sleep.

When sleep is disturbed, people sometimes cannot function normally during the day. People with insomnia or excessive daytime sleepiness are sleepy, tired, and irritable during the day and have trouble concentrating and functioning. People with excessive daytime sleepiness may fall asleep when working or driving.

There are different types of insomnia:

  • Difficulty falling asleep (sleep-onset insomnia): Commonly, people have difficulty falling asleep when they cannot let their mind relax and they continue to think and worry. Sometimes the body is not ready for sleep at what is considered a usual time for sleep. That is, the body’s internal clock is out of sync with the earth’s cycle of light and dark—as can occur with many types of circadian rhythm sleep disorders, such as delayed sleep phase disorder, shift work disorder, and jet lag.
  • Difficulty staying asleep and waking up earlier than desired (sleep maintenance insomnia): People with this type of insomnia fall asleep normally but wake up several hours later and cannot fall asleep again easily. Sometimes they drift in and out of a restless, unsatisfactory sleep. Sleep maintenance insomnia is more common among older people, who are more likely to have difficulty staying asleep than are younger people. It may occur in people who use certain substances (such as caffeine, alcohol, or tobacco) or who take certain drugs and in people who have certain sleep disorders (such as sleep apnea or periodic limb movement disorder). This type of insomnia may be a sign of depression in people of any age.

Causes of Insomnia and EDS

Insomnia and excessive daytime sleepiness may be caused by conditions inside or outside the body. Some conditions cause insomnia and excessive daytime sleepiness, and some cause one or the other. Some people have chronic insomnia that has little or no apparent relationship to any particular cause. Genetic factors may be involved.

Common causes

Insomnia is most often caused by

  • Poor sleep habits, such as drinking a caffeinated beverage in the late afternoon or evening, exercising late at night, or having an irregular sleep-wake schedule
  • Mental health disorders, particularly depression, anxiety, and substance abuse disorders
  • Other disorders such as heart and lung disorders, disorders that affect muscles or bones, or chronic pain
  • Stress, such as that due to hospitalization or loss of a job (called adjustment insomnia)
  • Excessive worrying about sleeplessness and another day of fatigue (called psychophysiologic insomnia)

Sleeping late or napping to make up for lost sleep may make sleeping during the next night even harder.

Excessive daytime sleepiness is most often caused by

  • Insufficient sleep despite having ample opportunity to sleep (called insufficient sleep syndrome)
  • Obstructive sleep apnea (a serious disorder in which breathing frequently stops during sleep)
  • Various disorders, particularly mental health disorders, brain or nerve (neurologic) disorders (such as encephalitis, meningitis, a brain tumor, or narcolepsy), and disorders that affect muscles or bones
  • Disorders that disrupt people's internal sleep-wake schedule (circadian rhythm disorders), such as jet lag and shift work disorder

Most major mental health disorders are accompanied by insomnia and excessive daytime sleepiness. About 80% of people with major depression have excessive daytime sleepiness and insomnia, and about 40% of people with chronic insomnia have a mental health disorder, usually depression or an anxiety disorder.

Any disorder that causes pain or discomfort, particularly if worsened by movement, can cause brief awakenings and interfere with sleep.

Less common causes

Drugs, when used for a long time or when stopped (withdrawal), can cause insomnia and excessive daytime sleepiness.

Some Drugs That Interfere With Sleep



When the drug is used

Antiseizure drugs


Chemotherapy drugs


Drugs that stimulate the brain



Beta blockers



Anabolic steroids


Thyroid hormone preparations

When the drug is stopped

Recreational drugs





Drugs that slow the brain




When the drug is used or stopped



Selective serotonin reuptake inhibitors (SSRIs), such as fluoxetine

Serotonin- norepinephrine reuptake inhibitors, such as duloxetine

Monoamine oxidase inhibitors (MAOIs), such as selegiline

Tricyclic antidepressants, such as amitriptyline

Many mind-altering (psychoactive) drugs can cause abnormal movements during sleep and may disturb sleep. Sedatives that are commonly prescribed to treat insomnia can cause irritability and apathy and reduce mental alertness. Also, if a sedative is taken for more than a few days, stopping the sedative can make the original sleep problem suddenly worse.

Sometimes the cause is a sleep disorder.

Central or obstructive sleep apnea is often first identified when people report insomnia or disturbed or unrefreshing sleep. It also occurs in people who have other disorders (such as a heart disorder) or who take certain drugs. Central or obstructive sleep apnea causes breathing to become shallow or to stop repeatedly throughout the night.

Narcolepsy is a sleep disorder characterized by excessive daytime sleepiness with uncontrollable episodes of falling asleep during normal waking hours and sudden, temporary episodes of muscle weakness (called cataplexy).

Periodic limb movement disorder interrupts sleep because it causes repeated twitching or kicking of the legs during sleep. As a result, people are sleepy during the day. Typically, people with periodic limb movement disorder are unaware of their movements and the brief awakenings that follow.

Restless legs syndrome makes falling and staying asleep difficult because people feel as if they have to move their legs and, less often, their arms when they sit still or lie down. People usually also have creepy, crawly sensations in the limbs.

Evaluation of Insomnia and EDS

Usually, the cause of insomnia can be identified based on the person's description of the current problem and results of a physical examination. Many people have obvious problems, such as poor sleep habits, stress, or coping with shift work.

Warning signs

Certain symptoms are cause for concern:

  • Falling asleep while driving or during other potentially dangerous situations
  • Frequently falling asleep without warning
  • Stopping breathing during sleep or waking up with gasping or choking (reported by a bed partner)
  • Moving violently or injuring self or others during sleep
  • Sleepwalking
  • A heart or lung disorder that is constantly changing (is unstable)
  • Attacks of muscle weakness (cataplexy attacks)
  • A recent stroke

When to see a doctor

People should see a doctor soon if they have warning signs or if their sleep-related symptoms interfere with their daily activities.

If healthy people have sleep-related symptoms for a short time (less than 1 or 2 weeks) but do not have warning signs, they can try changes in behavior that can help improve sleep. If these changes do not help after a week or so, people should see a doctor.

What the doctor does

The doctor asks people about the following:

  • Their sleep patterns
  • Habits around bedtime
  • Use of drugs (including recreational drugs)
  • Use of other substances (such as alcohol, caffeine, and tobacco)
  • Degree of stress
  • Medical history
  • Level of physical activity

People may be asked to keep a sleep log. In it, they record a detailed description of their sleep habits, with sleep and wake times (including awakening during the night), use of naps, and any problems with sleeping. When considering the diagnosis of insomnia, the doctor considers that some people need less sleep than others.

If people have excessive daytime sleepiness, the doctor may ask them to fill out a questionnaire, such as the Epworth Sleepiness Scale, indicating how likely they are to fall asleep in various situations. The doctor may ask their sleep partner to describe any abnormalities that occur during sleep, such as snoring and pauses in breathing.

Epworth Sleepiness Scale


Sitting and reading

Watching television

Sitting inactive in a public place

Riding as a car passenger for 1 hour continuously

Lying down to rest in the afternoon

Sitting and talking to someone

Sitting quietly after lunch (no alcohol)

Sitting in a car stopped for a few minutes in traffic

For this test, people use the following scale to rate their chances of dozing during certain situations:

  • None (0)
  • Slight (1)
  • Moderate (2)
  • High (3).

A score of 10 or more suggests abnormal daytime sleepiness.

A physical examination is done to check for disorders that can cause insomnia or excessive daytime sleepiness, particularly obstructive sleep apnea.


Tests are not needed if symptoms suggest a cause such as poor sleep habits, stress, shift work disorder, or restless leg syndrome (an irresistible urge to move the legs or arms just before or during sleep).

Doctors sometimes refer people to a sleep disorders specialist for evaluation in a sleep laboratory. Reasons for such a referral include

  • An uncertain diagnosis
  • Suspicion of certain disorders (such as sleep apnea, a seizure disorder, narcolepsy, and periodic limb movement disorder)
  • Insomnia or excessive daytime sleepiness persisting despite basic measures to correct it (changing behavior to improve sleep and taking sleep aids for a short time)
  • Presence of warning signs or other symptoms such as nightmares and twitching of the legs or arms during sleep
  • Dependence on sleep aids

The evaluation consists of polysomnography and observation (and sometimes video recording) of unusual movements during an entire night's sleep. Other tests are sometimes also done.

Polysomnography is usually done overnight in a sleep laboratory, which may be located in a hospital, clinic, hotel room, or other facility that is equipped with a bed, bathroom, and monitoring equipment. Electrodes are pasted to the scalp and face to record the brain's electrical activity (electroencephalography, or EEG) as well as eye movements. Applying these electrodes is painless. The recordings help provide doctors with information about sleep stages. Electrodes are also attached to other areas of the body to record heart rate (electrocardiography, or ECG), muscle activity (electromyography), and breathing. A painless clip is attached to a finger or an ear to record oxygen levels in the blood. Polysomnography can detect breathing disorders (such as obstructive or central sleep apnea), seizure disorders, narcolepsy, periodic limb movement disorder, and unusual movements and behaviors during sleep (parasomnias). Polysomnography is now commonly done in the home to diagnose obstructive sleep apnea, but not any other sleep disorders.

A multiple sleep latency test is done to distinguish between physical fatigue and excessive daytime sleepiness and to check for narcolepsy. People spend the day in a sleep laboratory. They are given the opportunity to take five naps at 2-hour intervals. They lie in a darkened room and are asked to take a nap. Polysomnography is used as part of this test to assess how quickly people fall asleep. It detects when people fall asleep and is used to monitor the stages of sleep during the naps.

The maintenance of wakefulness test is used to determine how well people can remain awake while sitting in a quiet room. This test helps determine how severe daytime sleepiness is and whether people can safely do their usual daily activities (such as driving a car).

Tests to evaluate the heart, lungs, and liver may be done in people with excessive daytime sleepiness if symptoms or results from the physical examination suggest that another disorder is the cause.

Treatment of Insomnia and EDS

Treatment of insomnia depends on its cause and severity but typically involves a combination of the following:

  • Treatment of disorders contributing to insomnia
  • Good sleep hygiene
  • Cognitive-behavioral therapy
  • Sleep aids

If insomnia results from another disorder, that disorder is treated. Such treatment may improve sleep. For example, if people have insomnia and depression, treating the depression often relieves the insomnia. Some antidepressant drugs also have sedative effects that help with sleep when the drugs are given before bed. However, these drugs may also cause daytime sleepiness, particularly in older people.

Good sleep hygiene is important whatever the cause and is often the only treatment patients with mild problems need.

But if daytime sleepiness and fatigue develop, especially if they interfere with daytime functioning, additional treatment is warranted, mainly counseling (cognitive-behavioral therapy) and sometimes prescription sleep aids or over-the-counter sleep aids. If people are considering taking an over-the-counter sleep aid, they should first talk to their doctor because these drugs can have significant side effects.

Alcohol is not an appropriate sleep aid and may actually interfere with sleep.

Sleep hygiene

Sleep hygiene focuses on changes in behavior to help improve sleep. These changes include limiting the amount of time spent in bed, establishing a regular sleep/wake schedule, and doing things to relax before going to bed (such as reading or taking a warm bath). Limiting the amount of time spent in bed is intended to help eliminate long periods of being awake in the middle of the night.

Changes in Behavior to Improve Sleep

What to Do

How to Do It

Follow a regular sleep-wake schedule

People should go to bed at the same time each night and, more importantly, get up at the same time each morning, even on weekends and vacations. People should not spend too much time in bed.

Follow a regular routine before bedtime

A regular pattern of activities—such as listening to soft music, brushing the teeth, washing the face, and setting the alarm clock—can set the mood for sleep. This routine should be followed every night, at home or away. As part of this routine, people should avoid bright lights before bedtime. Limiting use of a cell phone, computer, and television a few hours before bedtime can also help.

Make the environment conducive to sleep

The bedroom should be kept dark, quiet, and not too warm or too cold. Loud noises can disturb sleep even when people are not awakened by them. Wearing ear plugs, using a white-noise machine or a fan, or installing heavy curtains in the bedroom (to block out outside noises and light) can help. Wearing a mask over the eyes can help people who must sleep during daylight in a room that cannot be completely darkened. If people wake up during the night, they should avoid bright lights.

Use pillows

Pillows between the knees or under the waist can make some people more comfortable. For people with back problems, lying on the side with a large pillow between the knees or lying on the back with a large pillow under the knees may help.

Use the bed primarily for sleeping

The bed should be used for sleep and sex. It should not be used for eating, reading, watching television, paying bills, texting or emailing on a phone or laptop, or other activities associated with being awake.

Get up

When people are unable to fall asleep within 20 minutes, getting up and doing something else in another room and coming back to bed when sleepy may be more effective than lying in bed and trying harder and harder to fall asleep.

Exercise regularly

Exercise can help people fall asleep naturally. However, exercise within 5 hours of bedtime can stimulate the heart and brain and keep people awake.


Stress and worry interfere with sleep. People who are not sleepy at bedtime can relax by reading or taking a warm bath. Relaxation techniques, such as visual imagery, progressive muscle relaxation, and breathing exercises, can be used. People can aim to leave their problems at the bedroom door. Scheduling a worry time during the day to think about concerns can diminish the need to worry at bedtime.

Avoid stimulating activity before bedtime

Watching exciting television shows, playing thrilling computer games, or dealing with complicated work-related matters during the hour or so before bedtime can make sleeping difficult.

Avoid substances that interfere with sleep

Food and beverages that contain alcohol or caffeine (such as coffee, tea, cola drinks, and chocolate) can interfere with sleep, as can appetite suppressants, diuretics, and nicotine (in cigarettes and nicotine patches). Caffeinated substances should not be consumed within 12 hours of bedtime. Drinking a large amount of alcohol in the evening can cause early morning awakenings. Quitting smoking may help.

Eat a light snack if hungry

Hunger can interfere with going to sleep. Occasionally eating a light snack, especially if warm, can help, unless a person has gastroesophageal reflux. However, people should aim to stop eating at least a few hours before bedtime and not eat any meals, especially heavy meals, near bedtime. Heavy meals may cause heartburn, which can interfere with sleep.

Eliminate behaviors that provoke anxiety

People can turn the clock away so that time is not a focus. They should not watch the clock while they are in bed.

Spend time in bright light during the day

Exposure to light during the day can help people readjust their sleep-wake schedule to be in sync with the earth’s cycle of light and dark.

Avoid daytime naps, except for shift workers and people with narcolepsy

Daytime naps may interfere with sleeping at night in people with insomnia. However, naps reduce the need for drugs in people with narcolepsy and improve performance in shift workers. If needed, naps should be taken at the same time each day and limited to 30 minutes.

Cognitive-behavioral therapy

Cognitive-behavioral therapy, done by a trained sleep therapist, may help people when insomnia interferes with daily activities and when changes in behavior to help improve sleep (good sleep hygiene) alone are ineffective. Cognitive-behavioral therapy is typically done in four to eight individual or group sessions but can be done remotely through the Internet or by telephone.

The therapist helps people change their behavior to improve sleep. The therapist asks people to keep a sleep diary. In the diary, people record how well and how long they sleep as well as any behavior that might interfere with sleep (such as eating or exercising late at night, consuming alcohol or caffeine, feeling anxious, or being unable to stop thinking when trying to sleep).

Therapists may recommend limiting the amount of time spent in bed so that people spend less time lying in bed and trying unsuccessfully to sleep.

Cognitive-behavioral therapy can help people understand their problem, unlearn bad sleeping habits, and eliminate unhelpful thoughts, such as worrying about losing sleep or the next day’s activities. This therapy also includes relaxation training, which may involve techniques such as visual imagery, progressive muscle relaxation, and breathing exercises.

Prescription sleep aids

When a sleep disorder interferes with normal activities and a sense of well-being, occasionally taking prescription sleep aids (also called hypnotics or sleeping pills) for up to a few weeks may help.

Among the most commonly used sleep aids are sedatives, minor tranquilizers, and antianxiety drugs.

Most sleep aids require a doctor’s prescription because they may cause problems.

  • Loss of effectiveness: Once people become accustomed to a sleep aid, it may become ineffective. This effect is called tolerance.
  • Withdrawal symptoms: If a sleep aid is taken for more than a few days, stopping it suddenly can make the original sleep problem worse (causing rebound insomnia) and can increase anxiety. Thus, doctors recommend reducing the dose slowly over a period of several weeks until the drug is stopped.
  • Habit-forming or addiction potential: If people use certain sleep aids for more than a few days, they may feel that they cannot sleep without them. Stopping the drug makes them anxious, nervous, and irritable or causes disturbing dreams.
  • Potential for overdose: If taken in higher than recommended doses, some of the older sleep aids can cause confusion, delirium, dangerously slow breathing, a weak pulse, blue fingernails and lips, and even death.
  • Serious side effects: Most sleep aids, even when taken at recommended doses, are particularly risky for older people and for people with breathing problems because sleep aids tend to suppress areas of the brain that control breathing. Some can reduce daytime alertness, making driving or operating machinery hazardous. Sleep aids are especially dangerous when taken with other drugs that can cause daytime drowsiness and suppress breathing, such as alcohol, opioids (narcotics), antihistamines, or antidepressants. The combined effects are more dangerous. Rarely, especially if taken at higher than recommended doses or with alcohol, sleep aids have been known to cause people to walk or even drive during sleep and to cause severe allergic reactions. Sleep aids also increase the risk of falls at night.

Newer sleep aids can be used for longer periods of time without losing their effectiveness, becoming habit-forming, or causing withdrawal. They are also less dangerous if an overdose is taken.

Benzodiazepines are the most commonly used sleep aids. Some benzodiazepines (such as flurazepam) are longer acting than others (such as temazepam and triazolam). Doctors try to avoid prescribing long-acting benzodiazepines for older people. Older people cannot metabolize and excrete drugs as well as younger people. Thus for them, taking these drugs may be more likely to cause daytime drowsiness, slurred speech, falls, and occasionally confusion.

Other useful sleep aids are not benzodiazepines but affect the same areas of the brain as benzodiazepines. These drugs (eszopiclone, zaleplon, and zolpidem) are shorter acting than most benzodiazepines and are less likely to lead to daytime drowsiness. Older people appear to tolerate these drugs well. Zolpidem also comes in a longer-acting (extended-release, or ER) form and a very short acting (low-dose) form.

Ramelteon, a newer sleep aid, has the same advantages as these shorter-acting drugs. In addition, it can be used longer than benzodiazepines without losing its effectiveness or causing withdrawal symptoms. It is not habit-forming and does not appear to have overdose potential. However, it is not effective in many people. Ramelteon affects the same area of the brain as melatonin (a hormone that helps promote sleep) and is thus called a melatonin receptor agonist.

Suvorexant, a newer type of sleep aid, can also be used to treat insomnia.

Nonprescription sleep aids

Some sleep aids are available without a prescription (over-the-counter, or OTC), but an OTC sleep aid may be no safer than a prescription sleep aid, especially for older people. OTC sleep aids contain diphenhydramine or doxylamine, both antihistamines, which may have side effects, such as daytime drowsiness or sometimes nervousness, agitation, difficulty urinating, falls, and confusion, especially in older people.

OTC sleep aids that contain diphenhydramine should not be taken for more than 7 to 10 days. Usually, older people should not take these sleep aids. They are intended to manage an occasional sleepless night, not chronic insomnia, which could signal a serious underlying problem. If these drugs are used a long time or stopped abruptly, they may cause problems.

Melatonin is a hormone that helps promote sleep and that regulates the sleep-wake cycle. It can be used to treat insomnia. It may be effective when sleep problems are caused by consistently going to sleep and waking up late (for example, going to sleep at 3 AM and waking up at 10 AM or later)—called delayed sleep phase disorder. To be effective, melatonin should be taken when the body normally produces melatonin (the early evening for most people). Use of melatonin for insomnia is controversial but because it has few side effects, it is safe to use. It can be effective for short-term use (up to a few weeks), but the effects of using it for a long time are unknown. Also, melatonin products are unregulated, and thus purity and content cannot be confirmed. A doctor should supervise the use of melatonin.

Many other medicinal herbs and dietary supplements, such as skullcap and valerian, are available in health food stores, but their effects on sleep and their side effects are not well-understood.


Some antidepressants (such as paroxetine, trazodone, and trimipramine) can relieve insomnia and prevent early morning awakening when they are given in lower doses than those used to treat depression. These drugs may be used in the rare instances when people who are not depressed cannot tolerate other sleep aids. However, side effects, such as daytime sleepiness, can be a problem, especially for older people.

Doxepin, used as an antidepressant when given in high doses, may be an effective sleep aid when given in very low doses.

Essentials for Older People: Insomnia and Excessive Daytime Sleepiness

Because sleep patterns deteriorate as people age, older people are more likely to report insomnia than younger people. As people age, they tend to sleep less and to awaken more often during the night and to feel sleepier and to nap during the day. The periods of the deep sleep that are most refreshing become shorter and eventually disappear. Usually, these changes alone do not indicate a sleep disorder in older people.

Older people who have interrupted sleep can benefit from the following:

  • Regular bedtimes
  • Lots of exposure to light during the day
  • Regular exercise
  • Less napping during the day (because napping may make getting a good night’s sleep even harder)

Many older people with insomnia do not need to take sleep aids. But if they do, they should keep in mind that these drugs can cause problems. For example, sleep aids can cause confusion and reduce daytime alertness, making driving hazardous. Thus, caution is required.

Key Points about Insomnia and EDS

  • Poor sleep habits, stress, and conditions that disrupt people's internal sleep-wake schedule (such as shift work) cause many cases of insomnia and excessive daytime sleepiness.
  • However, sometimes the cause is a disorder, such as obstructive sleep apnea or a mental disorder.
  • Polysomnography done in a sleep laboratory or at home is usually recommended when doctors suspect the cause is obstructive sleep apnea or another sleep disorder, when the diagnosis is uncertain, or when general measures do not help.
  • If insomnia is mild, changes in behavior (good sleep hygiene), such as following a regular sleep schedule, may be all that is needed.
  • If changes in behavior are ineffective, cognitive-behavioral therapy is usually the next step, and, if needed, short-term use of a sleep aid (up to a few weeks) may be considered.
  • Sleep aids are more likely to cause problems in older people and can increase the risk of falls.

Drugs Mentioned In This Article

Generic Name Select Brand Names
diphenhydramine No US brand name
trimipramine Trimipramine
Propranolol INDERAL
eszopiclone LUNESTA
duloxetine CYMBALTA
selegiline ELDEPRYL
Suvorexant Suvorexant
doxylamine UNISOM
paroxetine PAXIL
fluoxetine PROZAC, SARAFEM
temazepam RESTORIL
trazodone OLEPTRO
Ramelteon ROZEREM
Phenytoin DILANTIN
triazolam HALCION
zaleplon SONATA
zolpidem AMBIEN

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