What Is Insomnia?
Insomnia can be a short-term or chronic condition, but it always involves problems with falling asleep or staying asleep. Short-term (transient) insomnia can be caused by illness, stress, travel, or environmental factors. Long-term (chronic) insomnia may be due to underlying psychological or physical conditions.
Who Is at Risk?
Anyone can get insomnia, but it is generally more common in women than in men. The elderly are particularly at risk for insomnia.
A doctor will make a diagnosis of insomnia based on information about your sleep patterns. Your doctor may ask:
Your doctor may also ask you to keep a sleep diary to record specific sleep-related information.
In 2011 the Food and Drug Administration (FDA) approved Intermezzo, a lower-dose form of zolpidem, for treating middle-of-the-night awakening. Patients who wake up abruptly in the middle of the night and then have trouble falling back asleep can dissolve the tablet under the tongue. People who use Intermezzo require at least 4 hours for sleep after taking the tablet. Higher-dose zolpidem pills (Ambien, generic) are used when first going to sleep and require at least 7 - 8 full hours of sleep.
Insomnia comes from the Latin words for “no sleep.” Insomnia is characterized by:
Insomnia may be primary or secondary:
Insomnia is often categorized by how long it lasts:
Insomnia may also be defined in terms of inability to sleep at conventional times. The following examples are referred to as circadian rhythm disorders:
In sleep studies, subjects spend about one-third of their time asleep, suggesting that most people need about 8 hours of sleep each day. Individual adults differ in the amount of sleep they need to feel well rested, however. (Infants may sleep as many as 16 hours a day.)
The daily cycle of life, which includes sleeping and waking, is called a circadian (meaning "about a day") rhythm, commonly referred to as the biologic clock. Hundreds of bodily functions follow biologic clocks, but sleeping and waking comprise the most prominent circadian rhythm. The sleeping and waking cycle is about 24 hours. It usually takes the following daily patterns:
In addition, daily rhythms intermesh with other factors that may interfere or change individual patterns:
The response to light signals in the brain is an important key factor in sleep:
Sleep consists of two distinct states that alternate in cycles and reflect differing levels of brain nerve cell activity:
Non-Rapid Eye Movement Sleep (NonREM). NonREM sleep is also termed quiet sleep. NonREM is further subdivided into three stages of progression:
With each descending stage, awakening becomes more difficult. It is not known what governs NonREM sleep in the brain. A balance between certain hormones, particularly growth and stress hormones, may be important for deep sleep.
Rapid Eye-Movement Sleep (REM). REM sleep is termed active sleep. Most vivid dreams occur in REM sleep. In REM sleep, brain activity is comparable to that in waking, but the muscles are virtually immobilized, which prevents people from acting out their dreams. In fact, except for vital organs like lungs and heart, the only muscles not immobilized during REM are the eye muscles. REM sleep may be critical for learning and for day-to-day mood regulation. When people are sleep-deprived, their brains must work harder than when they are well rested.
The REM/NREM Cycle. The cycle between quiet (nonREM) and active (REM) sleep generally follows this pattern:
A reaction to change or stress is a common cause of short-term and transient insomnia. This condition is sometimes referred to as adjustment sleep disorder.
The trigger could be a major or traumatic event such as:
Temporary insomnia can also develop after a relatively minor event, including:
In most cases, normal sleep almost always returns when the condition resolves, the individual recovers from the event, or the person becomes used to the new situation. Treatment is needed if sleepiness interferes with functioning or if it continues for more than a few weeks. Individual responses to stress vary and some people may not experience insomnia at all, even during very stressful situations while others may suffer from insomnia in response to very mild stressors.
Fluctuations in female hormones play a major role in insomnia in women over their lifetimes. This insomnia is usually temporary.
Air travel across time zones often causes insomnia. After long plane trips, a day of adjustment is usually needed for each time zone crossed. Traveling from the east to an earlier time zone in the west seems to be less disruptive than traveling to a later time zone in the east because it is easier to lengthen a circadian phase than to shorten it.
Light, noise, and uncomfortable temperatures can cause sleeplessness. Depending on the time of day, too much or too little light can disrupt sleep.
Caffeine. Caffeine is a stimulant, which can interfere with falling asleep.
Nicotine. Nicotine is also a stimulant, but quitting smoking can lead to transient insomnia.
Partner's Sleep Habits. A partner’s sleep habits, including snoring, can impair one’s own sleep.
Medications. Insomnia is a side effect of many common medications, including over-the-counter preparations that contain caffeine or decongestants. If you suspect your medications are causing you to lose sleep, check with your doctor or pharmacist.
Sleep problems seem to run in families. Many people with insomnia have a family history of insomnia, with the mother being the most commonly affected family member. Still, because so many factors are involved in insomnia, a genetic component is difficult to define.
Many cases of chronic insomnia cases have an emotional or psychological basis. The disorders that most often cause insomnia are:
Insomnia may also cause emotional and mental health problems, such as depression and anxiety. It is often unclear which condition has triggered the other, or if the two conditions, in fact, have a common source.
In many cases, it is unclear if chronic insomnia is a symptom of some physical or psychological condition or if it is a primary disorder of its own. In most instances, a mix of psychological and physical conditions causes the insomnia.
Psychophysiologic insomnia occurs when:
Among the many medical problems that can cause chronic insomnia are allergies, benign prostatic hyperplasia (BPH), arthritis, gastroesophageal reflux disease (GERD), asthma, chronic obstructive pulmonary disorder (COPD), rheumatologic conditions, Alzheimer's disease, Parkinson's disease, hyperthyroidism, epilepsy, and fibromyalgia. Other types of sleep disorders, such as restless legs syndrome and sleep apnea, can cause insomnia. Many patients with chronic pain also sleep poorly.
Medications. Among the many medications that can cause insomnia are antidepressants (fluoxetine, bupropion), theophylline, lamotrigine, felbamate, beta-blockers, and beta-agonists.
Substance abuse can cause chronic insomnia. This is especially true for alcohol, cocaine, and sedatives. One or two alcoholic drinks may help reduce stress and initiate sleep. However, excessive alcohol use tends to fragment sleep and cause wakefulness a few hours later. It also increases the risk for other sleep disorders, including sleep apnea and restless legs. Alcoholics often suffer insomnia during withdrawal and, in some cases, for several years during recovery.
More than a quarter of all Americans experience transient insomnia at some point during a year, and nearly 10% have chronic insomnia.
Overall, insomnia is more common in women than men, although men are not immune from insomnia. Sleep efficiency deteriorates equally in men and women as they get older.
Hormonal fluctuations that occur during menstruation, pregnancy, and menopause put women at higher risk of insomnia. Women are also more likely than men to suffer from anxiety and depressive disorders, which can cause insomnia.
Insomnia is more common in older people than younger people. As people grow older, sleep patterns change. Older adults tend to wake up frequently during the night, wake up earlier, and report waking up feeling unrefreshed.
Older people are more likely than younger people to have medical conditions that cause pain or nighttime distress. These conditions include arthritis, gastrointestinal distress, frequent urination, lung disease, and heart conditions. Neurologic conditions, such as Parkinson’s and Alzheimer’s, can also affect sleep patterns. Consequences of poor sleep in the elderly include increased risk of falls.
Shift workers are at considerable risk for insomnia. Workers over age 50 and those whose shifts are always changing are particularly susceptible to insomnia, although night-shift workers also have a high rate of sleeplessness. Night-shift workers are at risk for falling asleep on the job at least once a week, implying that their internal clocks do not adjust to unusual work times. (They are also at much higher risk than other workers for automobile accidents due to their drowsiness and may also have a higher risk for health problems in general.)
Insomnia itself is not life threatening, but it can increase the risk of accidents, psychiatric problems, and certain medical conditions, affect school and work performance, and significantly interfere with quality of life. Lack of sleep can cause weight gain and obesity.
Sleepiness increases the risk for motor vehicle accidents. Studies indicate that drowsy driving is as risky as drunk driving.
Surveys show that people with severe insomnia have a quality of life that is almost as poor as those who have chronic medical conditions, such as heart failure. Daytime sleepiness can lead to decreased energy, irritability, mistakes at work and school, and poorer relationships.
Insomnia makes it harder to concentrate and perform tasks. Deep sleep deprivation impairs the brain's ability to process information and reduces concentration.
Although stress and depression are major causes of insomnia, insomnia may also increase the activity of the hormones and pathways in the brain that are associated with mental health problems. Chronic insomnia may increase the risk of developing depression and anxiety.
Even modest alterations in waking and sleeping patterns can have significant effects on a person's mood. In both children and adults, the combination of insomnia and daytime sleepiness can produce more severe depression than either condition alone.
Having a doctor diagnose sleep disturbance and its cause is the most important step in restoring healthy sleep. However, there is little agreement, even among doctors, on the best methods for effectively assessing a patient's insomnia.
A number of questionnaires are available for determining whether a patient has insomnia or other sleep disorders. For example, the doctor may ask:
Sleep Diary. If the patient cannot answer these questions, keeping a sleep diary is a helpful diagnostic tool. Every day for 2 weeks, the patient should record all sleep-related information (including responses to questions listed above). Other information should include the time the patient went to bed, time spent falling asleep, number of nocturnal awakenings, and rising time. A bed partner's observations of the patient's sleep behavior can also help.
Actigraphy. Actigraphy uses a portable device with a sensor to monitor a patient's movement. Actigraphy may be used in some situations to help give a doctor a better picture of the patient's sleep pattern. It cannot, however, determine the severity of sleep problems. Most patients with insomnia are diagnosed and treated without this test. However, actigraphy may help identify insomnia in some patients.
If unexplained insomnia persists after treatment or there is evidence of a primary sleep disorder, such as sleep apnea or narcolepsy, the doctor may recommend a sleep specialist or a sleep disorders center. Centers are accredited by the American Academy of Sleep Medicine. Patients should investigate centers carefully, to be sure that they offer full sleep studies. [For more information, see In-Depth Report #65: Sleep apnea and #98: Narcolepsy.]
Among the signs that may indicate a need for a sleep disorders center are:
At most sleep disorders centers, patients undergo an in-depth analysis, usually supervised by a multidisciplinary team of consultants who can provide both physical and psychiatric evaluations.
The American Academy of Sleep Medicine (AASM) recommends a number of behavioral methods and prescription medications as the main treatments for insomnia. According to the AASM, these treatment options can improve both quality and quantity of sleep for people with insomnia.
Doctors agree that behavioral therapies should be the first-line treatment for insomnia. For children in particular, medications should rarely be used as initial treatment.
Proper sleep hygiene should accompany any behavioral method. The term sleep hygiene is used to describe simple behaviors that may help everyone improve their sleep. These include:
Various approaches are available to help people learn how to relax and sleep well. Behavioral techniques can actually cure chronic insomnia in many cases, and studies report that they help nearly all patients with primary chronic insomnia. The benefits of psychological and behavioral therapy in managing insomnia are long lasting.
Although medications can help people with insomnia to sleep, they cannot cure the condition. In addition, behavioral methods act faster. Behavioral methods work for all age groups, including children and elderly patients.
Behavioral methods include:
All behavioral approaches have the same basic goals:
Studies report that the majority of patients who are treated with non-drug methods experience improved sleep. Furthermore, most of those who have been taking drugs are able to stop or reduce their use.
Stimulus Control. Stimulus control is considered the standard treatment for primary chronic insomnia and may also be helpful for some patients with secondary insomnia. The primary goal of stimulus control is to regain the idea that the bed is for sleeping. It involves the following:
Cognitive-Behavioral Therapy. Cognitive behavioral therapy (CBT) is a form of therapy that emphasizes observing and changing negative thoughts about sleep such as, "I'll never fall asleep." It uses actions intended to change behavior. The goal is to change or correct misconceptions about the ability to fall and stay asleep. Emphasis is on reinforcing the need for 7 - 8 hours of sleep each night and addressing the anxiety that patients with insomnia often develop around sleep. Many studies have shown it to work as well or better than drugs. According to several studies, adding medication to CBT does not provide additional benefit.
Relaxation Training and Biofeedback. Relaxation training includes breathing and guided imagery techniques. Progressive muscle relaxation is another technique for inducing sleep that works well for many people. It takes about 10 minutes to perform:
Biofeedback may be combined with relaxation techniques. Biofeedback involves being monitored with an electroencephalogram (EEG), a device that measures brain waves. Patients are given feedback to recognize certain states of tension or sleep stages so that they can either avoid or repeat them voluntarily.
Paradoxical Intention and Sleep Restriction Therapies. Paradoxical intention is a type of cognitive technique that aims to conquer anxiety about insomnia by forcing the patient to stay awake. Not trying to fall asleep may help relieve performance anxiety associated with sleep.
Sleep restriction therapy is similar to paradoxical intention. It involves limiting the time spent in bed to the number of hours that are typically actually spent asleep. Eventually the sleep loss helps some people fall asleep faster and spend more time asleep. As sleep improves, the hours spent in bed are increased.
In general, the following considerations are important regarding the use of medications for the treatment of insomnia:
Many older Americans use some form of sleep aid pill, including prescription or over-the-counter drugs. Over-the-counter (nonprescription) medications make use of the drowsiness caused by some common medications. Prescription drugs used specifically for improving sleeping are called sedative hypnotics. These drugs include benzodiazepines and non-benzodiazepines.
Sedative hypnotics carry risks for dependence, tolerance, and rebound insomnia:
Brands with Antihistamines. Many over-the-counter sleeping medications use antihistamines, which cause drowsiness. Diphenhydramine (Benadryl, generic) is the most common antihistamine used in non-prescription sleep aids.
Some drugs marketed as sleep aids contain diphenhydramine alone, while others contain combinations of diphenhydramine with pain relievers (such as Tylenol PM and its generic forms). Doxylamine (Unison, generic) is another antihistamine used in sleep medications. Certain antihistamines indicated only for allergies, such as chlorpheniramine (Chlor-Trimeton, generic) or hydroxyzine (Atarax, Vistaril, generic) may also be used as mild sleep-inducers.
Unfortunately, most of these drugs leave patients feeling drowsy the next day and may not be very effective in providing restful sleep. Side effects include:
In general, people with angina, heart arrhythmias, glaucoma, or problems urinating should avoid these drugs. They should not be used at the same time as medications that prevent nausea or motion sickness. Patients with chronic lung disease should also avoid some non-prescription sleeping aids, such as those containing doxylamine.
Common Pain Relievers. When sleeplessness is caused by minor pain, simply taking acetaminophen (Tylenol, generic) or a non-steroidal anti-inflammatory drug (NSAID) such as ibuprofen (Advil, Motrin, generic), can be very helpful without causing any daytime sleepiness. The extra "P.M." antihistamine found in combination products is simply an extra, needless chemical in these situations.
Newer short-acting non-benzodiazepines can induce sleep with fewer side effects than benzodiazepines. Both benzodiazepine and non-benzodiazepine sedative hypnotics act on gamma-aminobutyric acid (GABA) receptor sites in the brain, but non-benzodiazepines are more specific in the subunits they target. These drugs are now the preferred sedative hypnotic drugs for the treatment of insomnia. In general, non-benzodiazepine hypnotics are recommended for short-term use (7 - 10 days), and treatment should not exceed 4 weeks.
Brands. Non-benzodiazepine hypnotics currently approved in the United States are:
Side Effects. All of these drugs have fewer morning side effects than the benzodiazepines, including morning sedation and memory loss (although they can occur to some degree). When patients first start taking any of these drugs, they should use caution during morning activities until they are sure how the drug affects them.
General side effects may include:
All non-benzodiazepine drugs carry labels warning that that these drugs can cause sleep-related behavior, including driving, making phone calls, and preparing and eating food while asleep. (Most cases of sleepwalking and sleep driving likely occur when patients use zolpidem along with alcohol or other drugs or take more than the recommended dose.) In addition, severe allergic reactions (anaphylaxis) and facial swelling (angioedema) can occur even the first time one of these drugs is taken.
Anyone who receives a prescription for these medicines will get a patient medication guide explaining the risks of the drugs and the precautions to take. Talk to your doctor if you have any questions concerning these drugs or their potential side effects.
Patients should carefully read the information labels for all drugs and follow the directions. Some sleeping pills take 30 - 60 minutes to take effect, while others (such as zolpidem) act quickly. For zolpidem, patients should:
Interactions. As with any hypnotics, alcohol increases the sedative effects of these drugs. These hypnotics also interact with other drugs, including rifampin, ketoconazole, erythromycin, and cimetidine. They may also interfere with or be interfered by other drugs. Patients should report all medications to their doctors.
Rebound Insomnia, Dependence, and Tolerance. The risk for rebound insomnia, dependence, and tolerance is lower with non-benzodiazepine hypnotics than with benzodiazepine drugs. These drugs are still subject to abuse. In any case, no hypnotic should be taken for more than 7 - 10 days or at higher than the recommended dose without a doctor's approval.
Benzodiazepines used to be the most commonly prescribed sedative hypnotics. Originally developed in the 1960s to treat anxiety, these drugs nonselectively target receptor sites in the brain that modulate the effects of the GABA neurotransmitter.
Brands. Commonly prescribed benzodiazepines:
Side Effects. Elderly people are more susceptible to side effects and should usually start at half the dose prescribed for younger people. They should not take long-acting forms.
Side effects may differ depending on whether the benzodiazepine is long or shorting acting. They include:
Interactions. Benzodiazepines are potentially dangerous when combined with alcohol. Some medications, like the ulcer medication cimetidine, can slow the metabolism of the benzodiazepine.
Withdrawal Symptoms. Withdrawal symptoms usually occur after prolonged use and indicate dependence. They can last 1 - 3 weeks after stopping the drug and may include:
Antidepressants are sometimes used to treat insomnia that may be caused by depression (secondary insomnia). In addition, certain types of antidepressants with sedating properties are prescribed for the treatment of primary insomnia, generally in lower doses than used to treat depression.
For example, the antidepressant trazodone (Desyrel, generic) is prescribed in low doses as a hypnotic to help induce sleep. A very low dose formulation of the tricyclic antidepressant doxepin (Silenor) is approved for treatment of insomnia. Other antidepressants used for insomnia include the tricyclics trimipramine (Surmontil, generic) and amitriptyline (Elavil, generic) and the tetracyclic antidepressant mirtazapine (Remeron, generic). Care should be taken in the use of trazodone and other sedating antidepressants in elderly patients, due to the risk for side effects (daytime sleepiness, dizziness, priapism, and increased risk of falls) and drug interactions.
More than 1.5 million Americans use complementary and alternative therapies to treat insomnia. Many people choose herbal and dietary supplement remedies. (Valerian and melatonin are among the most popular alternative remedies for insomnia.) Some, such as chamomile tea or lemon balm, are generally harmless for most people. Others have more serious side effects and interactions.
The American Academy of Sleep Medicine (AASM) advises that there is only limited scientific evidence to show that herbal and dietary supplements are effective sleep aids. The AASM recommends that these products should be taken only if approved by a doctor. Be sure to talk to your doctor if you are considering taking any herbal or dietary supplement. Some of these products can interact with prescription medications.
Generally, manufacturers of herbal remedies and dietary supplements do not need FDA approval to sell their products. Just like a drug, herbs and supplements can affect the body's chemistry, and therefore have the potential to produce side effects that may be harmful. There have been a number of reported cases of serious and even lethal side effects from herbal products. Patients should always check with their doctors before using any herbal remedies or dietary supplements.
Melatonin. Melatonin is the most studied dietary supplement for insomnia. It appears to reduce the time to fall asleep (sleep onset) and the time spent asleep (sleep duration). However, there are no consistent standards on melatonin doses. Some research suggests that 0.3 mg may be the most effective dosage in many people with insomnia. However, higher doses may keep some people awake and may also cause mental impairment, severe headaches, and nightmares. Although melatonin may not have many benefits for most people with chronic insomnia, studies suggest that it may help travelers with jet lag and people with delayed sleep syndrome.
Valerian root. Valerian is an herb that has sedative qualities and is commonly used by people with insomnia. Some studies have indicated that it may help improve the quality of sleep, but there have been few rigorous and well-conducted trials to prove it is effective.
Kava. Kava has been used to relieve anxiety and improve sleep. It is dangerous. There have been reports of liver failure and death from this herb, with highest risk in those with liver disease. Kava can interact dangerously with certain medications, including alprazolam, an anti-anxiety drug. Kava also increases the strength of certain other drugs, including other sleep medications, alcohol, and antidepressants. Do not use this herb.
Tryptophan and 5-L-5-hydroxytryptophan (HTP). Tryptophan is an amino acid used in the formation of the neurotransmitter serotonin, which is associated with healthy sleep. L-tryptophan used to be marketed for insomnia and other disorders but was withdrawn after contaminated batches caused a rare but serious and even fatal disorder called eosinophilia myalgia syndrome. 5-HTP, a byproduct of tryptophan, is still available as a supplement. There is little evidence that 5-HTP relieves insomnia.
Bent S, Padula A, Moore D, Patterson M, Mehling W. Valerian for sleep: a systematic review and meta-analysis. Am J Med. 2006 Dec;119(12):1005-12.
Bliwise DL, Ansari FP. Insomnia associated with valerian and melatonin usage in the 2002 National Health Interview Survey. Sleep. 2007 July 1;30(7):881-884.
Centers for Disease Control and Prevention (CDC). Perceived insufficient rest or sleep among adults - United States, 2008. MMWR Morb Mortal Wkly Rep. 2009 Oct 30;58(42):1175-9.
Kamel NS, Gammack JK. Insomnia in the elderly: cause, approach, and treatment. Am J Med. 2006 Jun;119(6):463-9.
Morgenthaler T, Alessi C, Friedman L, Owens J, Kapur V, Boehlecke B, et al. Practice parameters for the use of actigraphy in the assessment of sleep and sleep disorders: an update for 2007. Sleep. 2007 Apr 1;30(4):519-29.
Morin CM, Bélanger L, LeBlanc M, Ivers H, Savard J, Espie CA, et al. The natural history of insomnia: a population-based 3-year longitudinal study. Arch Intern Med. 2009 Mar 9;169(5):447-53.
Morin CM, Benca R. Chronic insomnia. Lancet. 2012 Mar 24;379(9821):1129-41. Epub 2012 Jan 20.
Morgenthaler T, Kramer M, Alessi C, Friedman L, Boehlecke B, Brown T, et al. Practice parameters for the psychological and behavioral treatment of insomnia: an update. An American Academy of Sleep Medicine report. Sleep. 2006 Nov 1;29(11):1415-9.
Morin CM, Bootzin RR, Buysse DJ, Edinger JD, Espie CA, Lichstein KL. Psychological and behavioral treatment of insomnia: update of the recent evidence (1998-2004). Sleep. 2006 Nov 1;29(11):1398-414.
Neckelmann D, Mykletun A, Dahl AA. Chronic insomnia as a risk factor for developing anxiety and depression. Sleep. 2007 July 1;30(7):873-880.
Parish JM. Sleep-related problems in common medical conditions. Chest. 2009 Feb;135(2):563-72.
Ramakrishnan K, Scheid DC. Treatment options for insomnia. Am Fam Physician. 2007 Aug 15;76(4):517-26.
Schutte-Rodin S, Broch L, Buysse D, Dorsey C, Sateia M. Clinical guideline for the evaluation and management of chronic insomnia in adults. J Clin Sleep Med. 2008 Oct 15;4(5):487-504.
Taibi DM, Landis CA, Petry H, Vitiello MV. A systematic review of valerian as a sleep aid: safe but not effective. Sleep Med Rev. 2007 Jun;11(3):209-30.
van Straten A, Cuijpers P. Self-help therapy for insomnia: a meta-analysis. Sleep Med Rev. 2009 Feb;13(1):61-71. Epub 2008 Oct 26.
Wilson JF. In the clinic. Insomnia. Ann Intern Med. 2008 Jan 1;148(1):ITC13-1-ITC13-16.
Reviewed By: Harvey Simon, MD, Editor-in-Chief, Associate Professor of Medicine, Harvard Medical School; Physician, Massachusetts General Hospital. Also reviewed by David Zieve, MD, MHA, Medical Director, A.D.A.M. Health Solutions, Ebix, Inc.