Insomnia is a common sleep disorder that makes it hard to fall asleep, stay asleep, or wake up feeling rested, even when there is enough time and a reasonable chance to sleep. Almost everyone has a rough night now and then, and short bouts of insomnia brought on by stress or a change in routine are normal and usually pass on their own. For some people, though, the pattern settles in and continues for months, leaving them tired, foggy, and irritable during the day. The reassuring part is that insomnia is well understood and highly treatable, most often without medication at all. This guide explains what insomnia is, its symptoms, causes, how it is diagnosed, the treatments available, and the latest research.
What is insomnia?
Insomnia is trouble falling asleep, staying asleep, or waking up too early and being unable to get back to sleep, despite having adequate time and a reasonable environment for rest. It is considered a disorder once it also causes daytime problems such as fatigue, low mood, irritability, or trouble concentrating. Short-term, or acute, insomnia lasts from a few days to a few weeks and is often triggered by an identifiable stress, a change in schedule, or travel. Chronic insomnia is diagnosed when sleep trouble occurs at least three nights a week for three months or longer, no matter what first set it off.
Insomnia is one of the most common health complaints in the United States. National survey data found that 14.5 percent of US adults had trouble falling asleep and 17.8 percent had trouble staying asleep on most days or every day in the past month. Roughly 10 percent of adults have chronic insomnia, and about 1 in 3 adults worldwide report at least occasional symptoms. Trouble sleeping is reported more often by women, by adults between the ages of 45 and 64, and by people with lower income or less education, although insomnia can affect anyone at any age.
Symptoms of insomnia
The core symptoms of insomnia happen at night: difficulty falling asleep, waking up repeatedly during the night, waking too early and being unable to fall back asleep, and sleep that feels light or unrefreshing even after enough hours in bed. These patterns can vary from night to night, and many people with insomnia also spend time lying awake worrying about not being able to sleep, which itself can make falling asleep harder.
Because insomnia limits restorative sleep, its effects often show up during the day as much as at night. Common daytime symptoms include fatigue and low energy, trouble concentrating or remembering things, irritability or low mood, tension headaches, and daytime sleepiness that can affect work, school, or driving safety. When these daytime effects persist alongside ongoing sleep trouble, they are part of what separates insomnia disorder from an occasional bad night.
What causes insomnia and its risk factors
Insomnia often has more than one cause layered together. Stress is one of the most common triggers, and recognizing the persistent worry of anxiety or identifying the low mood and fatigue of depression helps explain why so many cases are tied to mental health, since about half of people with chronic insomnia also have a co-occurring mental health condition. Poor sleep habits contribute as well, including irregular bedtimes and wake times, using screens in bed, napping late in the day, and drinking caffeine or alcohol in the evening. Shift work and jet lag can also disrupt the body’s internal clock enough to cause lasting sleep trouble.
Certain medications can interfere with sleep, including some antidepressants, asthma medications, and over-the-counter products that contain stimulants. Medical conditions are common contributors too, among them chronic pain, restless legs syndrome, sleep apnea, thyroid disorders, gastroesophageal reflux disease, and the hormonal shifts of menopause. Because insomnia so often overlaps with another condition, identifying and treating that underlying issue is frequently a key part of getting sleep back on track.
How insomnia is diagnosed
Insomnia is diagnosed clinically, based on a detailed medical history, a physical exam, and questions about sleep patterns, habits, and daytime symptoms, rather than a single definitive test. Because self-reported patterns can be hard to pin down from memory alone, doctors often ask patients to track their sleep for one to two weeks before or during the evaluation, and sometimes add an objective measurement to confirm the pattern.
| Assessment | What it involves |
|---|---|
| Sleep history and exam | A doctor reviews sleep patterns, habits, medications, and daytime symptoms in detail |
| Sleep diary | A 1- to 2-week record of bedtime, wake time, naps, and caffeine or alcohol use |
| Actigraphy | A wrist-worn motion sensor worn for 3 to 14 days to estimate sleep and wake timing |
| Polysomnography (sleep study) | An overnight, in-lab study reserved for suspected sleep apnea, narcolepsy, or a circadian rhythm disorder |
Because insomnia has no laboratory test of its own, blood work plays a supporting role, mainly to identify or rule out a medical contributor rather than to confirm the diagnosis itself. Part of that workup can involve ruling out the accelerated metabolism of hyperthyroidism or investigating the breathing pauses of sleep apnea, two conditions that can resemble or worsen insomnia but are treated differently from it. When a contributor is suspected, a doctor may also order tests checking the thyroid-stimulating hormone measured by a TSH test, evaluating the cortisol level that reflects the body’s stress response, and measuring the magnesium level involved in nerve and muscle function, since imbalances in any of these can disturb sleep. A normal result does not rule out insomnia itself, but it helps confirm that the sleep trouble is primary rather than a sign of something else. Learning how flags and reference ranges on a lab report translate into next steps can make any of these results easier to discuss with your doctor.
Treatment options for insomnia
Cognitive behavioral therapy for insomnia, known as CBT-I, is recommended as the first treatment for chronic insomnia and works as well as or better than medication, with benefits that tend to last longer once treatment ends. It is a structured, multi-week program that addresses the habits and thought patterns that keep insomnia going, rather than simply sedating the brain for a single night. For short-term insomnia, addressing the trigger and practicing good sleep habits is often enough on its own.
| Approach | Role |
|---|---|
| CBT-I | First-line treatment; retrains sleep habits and the thoughts that fuel nighttime worry, with effects that often outlast medication |
| Sleep hygiene and habit changes | Supports other treatments by building a consistent routine and limiting evening caffeine, alcohol, and screens |
| Dual orexin receptor antagonists | Newer prescription medications that promote sleep by blocking wake-signaling brain chemicals rather than broadly sedating |
| Other sleep medications | Older sedative-hypnotics that can help short-term but carry more risk of dependency and side effects with ongoing use |
Medication can play a role, particularly for short-term insomnia or alongside CBT-I, but it is generally intended for careful, time-limited use because of the risk of dependency and side effects with some older drugs. A newer class of medication, dual orexin receptor antagonists, works differently from older sedative-hypnotics and has a growing evidence base, including in older adults. Because CBT-I and medication work in different ways, a clinician can help decide whether therapy alone, medication alone, or a combination best fits a particular situation.
Living with insomnia and long-term outlook
Most people with insomnia see meaningful improvement once they start treatment, especially with CBT-I, and many go on to manage occasional rough patches on their own after they have learned the underlying skills. Insomnia can come and go over a lifetime, often flaring during stressful periods or major life changes, but a previous episode does not mean the next one will be as severe or as hard to treat. Recognizing early signs, such as a slide back into irregular sleep habits or renewed worry about sleep, allows small adjustments before the pattern becomes entrenched again.
Ongoing habits make a real difference in staying well: keeping a consistent sleep and wake schedule, reserving the bed for sleep, limiting evening caffeine and alcohol, and getting daylight and physical activity during the day. Because untreated chronic insomnia is linked to a higher risk of anxiety, depression, and other health problems over time, it is worth continuing to address sleep rather than simply living around it. With an effective plan in place, most people with insomnia sleep well enough to feel like themselves again during the day.
Latest scientific advances in insomnia research
Recent research has focused on how best to combine insomnia’s two main treatment tracks, behavioral therapy and medication, and on expanding access to first-line care. According to PubMed-indexed research, a 2026 American Academy of Sleep Medicine clinical practice guideline reaffirmed cognitive behavioral therapy for insomnia as the most effective first-line treatment, conditionally recommending CBT-I plus medication over medication alone but recommending against routinely adding medication on top of CBT-I when CBT-I alone is an option (Buysse et al., 2026). What this means for you: starting with CBT-I still offers the best chance of lasting improvement, and adding a sleep medication is a matter of personal preference rather than a routine upgrade. A related 2026 systematic review and meta-analysis of five randomized controlled trials, involving 309 people using digital CBT-I and 249 receiving a control condition, found that app- and web-delivered CBT-I produced a moderate-to-large reduction in insomnia severity that was maintained for up to twelve months (Rawcliffe and Pereira, 2026). What this means for you: if a trained CBT-I therapist is not available nearby, a well-designed digital program can deliver the same first-line treatment with results that last.
Medication research has also advanced, especially for older adults, who tend to be more sensitive to the side effects of older sleep aids. A 2026 systematic review and meta-analysis pooling data from 2,235 older adults treated with a dual orexin receptor antagonist and 1,409 given a control treatment found that these medications reduced the time spent awake after falling asleep and the time it took to fall asleep, while increasing total sleep time at one and three months; among the three approved drugs, daridorexant showed the most favorable side-effect profile, while the other two had somewhat higher rates of non-serious side effects than placebo (Rollo et al., 2026). What this means for you: for older adults who need medication alongside or instead of therapy, dual orexin receptor antagonists are a well-studied option, though which specific drug is used can affect how well it is tolerated, which is worth discussing with a doctor.
Glossary of key insomnia terms
| Term | Definition |
|---|---|
| Chronic insomnia | Trouble falling or staying asleep at least three nights a week for three months or longer. |
| Acute insomnia | Short-term sleep trouble lasting days to a few weeks, often tied to a clear trigger such as stress or travel. |
| Sleep diary | A daily record of bedtime, wake time, naps, and habits used to document sleep patterns. |
| Actigraphy | A wrist-worn sensor that estimates sleep and wake timing from movement over several days. |
| Polysomnography | An overnight, in-lab sleep study used when another disorder, such as sleep apnea, is suspected. |
| CBT-I | Cognitive behavioral therapy for insomnia, a structured program that changes sleep habits and thoughts about sleep. |
| Dual orexin receptor antagonist | A newer type of sleep medication that blocks wake-promoting brain chemicals instead of broadly sedating the brain. |
Frequently asked questions about insomnia
What is the difference between acute and chronic insomnia?
Acute insomnia is short-term, lasting from a few days to a few weeks, and is usually triggered by an identifiable cause such as stress, travel, or a change in schedule. Chronic insomnia means trouble falling asleep, staying asleep, or waking too early at least three nights a week for three months or more, regardless of what originally triggered it. Chronic insomnia usually calls for a more structured treatment approach, most often CBT-I.
What causes insomnia?
Insomnia usually results from a combination of factors, including stress, anxiety, and depression, poor sleep habits, shift work or jet lag, certain medications, and medical conditions such as chronic pain, restless legs syndrome, sleep apnea, and thyroid problems. About half of people with chronic insomnia also have a co-occurring mental health condition, which is why treatment often addresses both together.
How is insomnia diagnosed, and will I need a sleep study?
Insomnia is diagnosed clinically through a medical history, a physical exam, and questions about sleep patterns and daytime symptoms, often supported by a one- to two-week sleep diary. Most people do not need a sleep study; polysomnography is reserved for cases where another disorder, such as sleep apnea or narcolepsy, is suspected.
What blood tests check for causes of insomnia?
No blood test diagnoses insomnia itself, but a doctor may order tests such as thyroid-stimulating hormone, cortisol, or magnesium to look for a medical contributor to poor sleep. These tests are most useful when insomnia does not respond to initial treatment or when other symptoms suggest an underlying condition.
What is the first-line treatment for insomnia?
Cognitive behavioral therapy for insomnia, or CBT-I, is the recommended first treatment for chronic insomnia. It works as well as or better than medication over time, with benefits that tend to last after treatment ends, and it is increasingly available through app- and web-based programs as well as in-person therapists.
What are dual orexin receptor antagonists?
Dual orexin receptor antagonists are a newer class of prescription sleep medication that block wake-promoting brain chemicals rather than broadly sedating the brain. Research shows they can reduce the time it takes to fall asleep and increase total sleep time, including in older adults, though the approved drugs differ somewhat in side-effect profile.
Sources
- National Heart, Lung, and Blood Institute — Insomnia — NHLBI, National Institutes of Health, 2024 — nhlbi.nih.gov
- MedlinePlus, National Library of Medicine — Insomnia — MedlinePlus, 2024 — medlineplus.gov
- Mayo Clinic — Insomnia: Diagnosis and Treatment — Mayo Clinic, 2023 — mayoclinic.org
- Buysse DJ, et al. — Combination treatment for chronic insomnia disorder in adults: an American Academy of Sleep Medicine clinical practice guideline — Journal of Clinical Sleep Medicine, 2026 — doi.org/10.1007/s44470-025-00038-8
- Rollo E, et al. — Treatment of chronic insomnia in elderly adults with dual orexin receptor antagonists: a systematic review and meta-analysis — Sleep, 2026 — doi.org/10.1093/sleep/zsag135
- Rawcliffe AJ, Pereira SIR — Efficacy of digital cognitive behavioural therapy for insomnia in Armed Forces and Veteran populations – A systematic review and meta-analysis of randomised controlled trials — Sleep Medicine, 2026 — doi.org/10.1016/j.sleep.2026.108974
Further reading
- See what a thyroid hormone reveals about sleep and energy in this guide to the TSH blood test.
- Learn how a stress hormone can affect rest in this guide to the cortisol blood test.
- Understand a mineral tied to nerve and muscle relaxation in this guide to the magnesium blood test.
- Explore a condition that shares insomnia’s daytime fatigue in this guide to the overlap with chronic fatigue syndrome.
- Build confidence reading test results with this guide to reference ranges, flags, and next steps on a lab report.
Understand your lab results with BloodSense
Insomnia itself is not confirmed with a lab test, but the blood work that sometimes comes with an insomnia workup, including thyroid, cortisol, and magnesium levels, can reveal a treatable contributor to poor sleep or help rule one out with more confidence. Seeing where each value falls against its reference range makes those results easier to discuss with your doctor, especially when sleep problems overlap with fatigue, mood changes, or other symptoms.
