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Insomnia and Excessive Daytime Sleepiness (EDS)


Richard J. Schwab

, MD, University of Pennsylvania, Division of Sleep Medicine

Reviewed/Revised May 2022 | Modified Dec 2023
Topic Resources
  • 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.

Insomnia can be a disorder or can be a symptom of other disorders. Excessive daytime sleepiness is not a disorder but a symptom of various sleep-related disorders.

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 Overview of Sleep Sleep is necessary for survival and good health, but why sleep is needed and exactly how it benefits people are not fully understood. One of sleep's benefits is its restorative effect on people's... read more 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:

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, loss of a job, or a death in the family (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

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.


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 Central sleep apnea Sleep apnea is a serious disorder in which breathing repeatedly stops long enough to disrupt sleep and often temporarily decrease the amount of oxygen and increase the amount of carbon dioxide... read more Central 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.

Periodic limb movement disorder Periodic Limb Movement Disorder (PLMD) and Restless Legs Syndrome (RLS) Periodic limb movement disorder involves repetitive movements of the arms, legs, or both during sleep. Restless legs syndrome involves an irresistible urge to move and usually abnormal sensations... read more 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 Periodic Limb Movement Disorder (PLMD) and Restless Legs Syndrome (RLS) Periodic limb movement disorder involves repetitive movements of the arms, legs, or both during sleep. Restless legs syndrome involves an irresistible urge to move and usually abnormal sensations... read more 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:

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 Sleep hygiene 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... read more 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 (including disorders that can interfere with sleep)

  • Level of physical activity

Disorders that interfere with sleep include chronic obstructive pulmonary disease (COPD) Chronic Obstructive Pulmonary Disease (COPD) Chronic obstructive pulmonary disease is persistent narrowing (blocking, or obstruction) of the airways occurring with emphysema, chronic obstructive bronchitis, or both disorders. Cigarette... read more Chronic Obstructive Pulmonary Disease (COPD) , asthma Asthma Asthma is a condition in which the airways narrow—usually reversibly—in response to certain stimuli. Coughing, wheezing, and shortness of breath that occur in response to specific triggers are... read more Asthma , heart failure Heart Failure (HF) Heart failure is a disorder in which the heart is unable to keep up with the demands of the body, leading to reduced blood flow, back-up (congestion) of blood in the veins and lungs, and/or... read more Heart Failure (HF) , an overactive thyroid gland (hyperthyroidism Hyperthyroidism Hyperthyroidism is overactivity of the thyroid gland that leads to high levels of thyroid hormones and speeding up of vital body functions. Graves disease is the most common cause of hyperthyroidism... read more Hyperthyroidism ), gastroesophageal reflux Gastroesophageal Reflux Disease (GERD) In gastroesophageal reflux disease, stomach contents, including acid and bile, flow backward from the stomach into the esophagus, causing inflammation in the esophagus and pain in the bottom... read more Gastroesophageal Reflux Disease (GERD) , painful disorders (such as rheumatoid arthritis Rheumatoid Arthritis (RA) Rheumatoid arthritis is an inflammatory arthritis in which joints, usually including those of the hands and feet, are inflamed, resulting in swelling, pain, and often destruction of joints.... read more Rheumatoid Arthritis (RA) ), disorders that cause urinary incontinence Urinary Incontinence in Adults Urinary incontinence is involuntary loss of urine. Incontinence can occur in both men and women at any age, but it is more common among women and older adults, affecting about 30% of older women... read more Urinary Incontinence in Adults or frequent urination, and brain, spinal cord, and nerve disorders (particularly movement disorders Overview of Movement Disorders Every body movement, from raising a hand to smiling, involves a complex interaction between the central nervous system (brain and spinal cord), nerves, and muscles. Damage to or malfunction... read more ).

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 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.

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

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 Electroencephalography Diagnostic procedures may be needed to confirm a diagnosis suggested by the medical history and neurologic examination. Imaging tests commonly used to diagnose nervous system (neurologic) disorders... read more 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 Electrocardiography Electrocardiography (ECG) is a quick, simple, painless medical test that measures the heart’s electrical impulses. During an ECG, the heart's electrical impulses are measured, amplified, and... read more Electrocardiography , or ECG), muscle activity (electromyography Electromyography and Nerve Conduction Studies Diagnostic procedures may be needed to confirm a diagnosis suggested by the medical history and neurologic examination. Imaging tests commonly used to diagnose nervous system (neurologic) disorders... read more Electromyography and Nerve Conduction Studies ), 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.

Alcohol is not an appropriate sleep aid and may actually interfere with sleep. It produces an unrefreshing sleep with many awakenings during the night.

Does Exercise Help Decrease Insomnia?

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.


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 effects of this therapy last a long time after therapy ends.

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.

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.

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. 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.

Three relatively new drugs (daridorexant, lemborexant, and suvorexant) can be used to treat insomnia. They help people fall asleep and help them stay asleep. These drugs block orexin receptors in the brain that are involved in controlling sleep. Thus, they are called orexin receptor blockers (antagonists). They are taken by mouth once a day shortly before going to bed. However, these drugs are not overly effective for treating insomnia. The most common side effect is drowsiness.

Over-the-counter sleep aids

Some sleep aids that are available without a prescription (over-the-counter, or OTC) contain antihistamines (such as doxylamine and diphenhydramine). Antihistamines Allergic reactions (hypersensitivity reactions) are inappropriate responses of the immune system to a normally harmless substance. Usually, allergies cause sneezing, watery and itchy eyes, a... read more Antihistamines However, the drugs that contain antihistamines should not be taken to treat insomnia. Antihistamines may have significant side effects, such as daytime drowsiness or sometimes nervousness, agitation, difficulty urinating, falls, and confusion, especially in older people.

Melatonin Melatonin Melatonin, a hormone produced by the pineal gland (located in the middle of the brain), regulates the sleep-wake cycle. Melatonin used in supplements can be derived from animals, but most is... read more 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. Side effects include headache, dizziness, nausea, and drowsiness. Melatonin 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.

  • CBD (cannabidiol), which causes drowsiness but no euphoria

  • THC (tetrahydrocannabinol), which causes euphoria, reduces pain and nausea, and affects sleep stages

  • CBN (cannabinol), which causes drowsiness, reduces pain, and increases appetite

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 Medications for Treatment of Depression Several types of medications can be used to treat depression: Selective serotonin reuptake inhibitors (SSRIs) Norepinephrine-dopamine reuptake inhibitors, serotonin modulators, and serotonin-norepinephrine... read more (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 EDS

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

  • 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
Cafcit, NoDoz, Stay Awake, Vivarin
Ambien, Ambien CR, Edluar, Intermezzo, Zolpimist
Aldex AN, Doxytex, Unisom
Aid to Sleep, Alka-Seltzer Plus Allergy, Aller-G-Time , Altaryl, Banophen , Benadryl, Benadryl Allergy, Benadryl Allergy Children's , Benadryl Allergy Dye Free, Benadryl Allergy Kapgel, Benadryl Allergy Quick Dissolve, Benadryl Allergy Ultratab, Benadryl Children's Allergy, Benadryl Children's Allergy Fastmelt, Benadryl Children's Perfect Measure, Benadryl Itch Stopping, Ben-Tann , Children's Allergy, Compoz Nighttime Sleep Aid, Diphedryl , DIPHEN, Diphen AF , Diphenhist, DiphenMax , Dytan, ElixSure Allergy, Genahist , Geri-Dryl, Hydramine, Itch Relief , M-Dryl, Nighttime Sleep Aid, Nytol, PediaCare Children's Allergy, PediaCare Nighttime Cough, PediaClear Children's Cough, PHARBEDRYL, Q-Dryl, Quenalin , Siladryl Allergy, Silphen , Simply Sleep , Sleep Tabs, Sleepinal, Sominex, Sominex Maximum Strength, Theraflu Multi-Symptom Strip, Triaminic Allergy Thin Strip, Triaminic Cough and Runny Nose Strip, Tusstat, Unisom, Uni-Tann, Valu-Dryl , Vanamine PD, Vicks Qlearquil Nighttime Allergy Relief, Vicks ZzzQuil Nightime Sleep-Aid
Epidiolex Solution
Marinol, SYNDROS
No brand name available
Brisdelle, Paxil, Paxil CR, Pexeva
Desyrel, Oleptro
Prudoxin, Silenor, Sinequan, Zonalon
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