Insomnia: Causes, Symptoms and Treatment That Works

Quick answer

CBT-I is the first-line treatment; pills are short-term

Short-term insomnia is usually linked to stress and settles in days or weeks. Chronic insomnia means trouble sleeping at least three nights a week for three months, with daytime effects such as fatigue, poor concentration or low mood. The American College of Physicians and other guidelines recommend CBT-I as first-line therapy, because it works as well as medication in the short term and better in the long term. Sleep habits, treating contributing conditions (pain, anxiety, apnoea, restless legs) and a short, supervised course of medication in selected cases complete the approach.

Important. Loud snoring with pauses in breathing, extreme daytime sleepiness, thoughts of self-harm, severe low mood or reliance on alcohol or sedatives to sleep need medical attention. If you are in crisis or thinking about harming yourself, seek help right away: in the US call or text 988, in the UK call Samaritans on 116 123, in Spain call 024, or call your local emergency number.

What is insomnia?

Insomnia involves one or more of: difficulty falling asleep (taking longer than 30 minutes), difficulty staying asleep (waking in the night and being unable to return to sleep) and early morning awakening, even though there is adequate opportunity to sleep. To count as insomnia, it must cause distress or daytime problems: tiredness, irritability, trouble concentrating, headaches, low mood or reduced performance.

About one in three adults has some symptoms of insomnia, and about 10% have chronic insomnia disorder. It is more common in women, older adults and people with stress, physical illness or mental health conditions.

Short-term and chronic insomnia

Short-term (acute) insomnia: lasts days to a few weeks and is usually triggered by stress, illness, travel, a noisy environment or life events.
Chronic insomnia disorder: occurs at least three nights a week for at least three months. It often continues because of habits and worries about sleep even after the original trigger has gone.
Sleep-onset, sleep-maintenance and early-waking patterns can occur separately or together.

Causes and contributing factors

Stress, worry and anxiety; depression and other mental health conditions.
Poor sleep habits: irregular schedules, long daytime naps, late caffeine or alcohol, screens and work in bed.
Environment: noise, light, heat, an uncomfortable mattress.
Medical conditions: chronic pain, reflux, asthma, heart failure, thyroid disease, menopause symptoms, sleep apnoea, restless legs syndrome.
Medicines and substances: some antidepressants, steroids, decongestants, stimulants, caffeine, nicotine, alcohol.
Shift work and jet lag.
Conditioned arousal: after weeks of poor sleep, the bed itself becomes associated with wakefulness and worry.

How insomnia is assessed

A clinician will ask about your sleep pattern, daytime symptoms, habits, medicines, mood and medical history, and may ask you to keep a sleep diary for one to two weeks. Questionnaires such as the Insomnia Severity Index help measure severity. Blood tests or a sleep study are not needed for most people, but may be advised if there are signs of sleep apnoea, restless legs, a movement disorder or a medical cause.

CBT for insomnia (CBT-I)

CBT-I is a structured programme, usually of 4–8 sessions, that targets the thoughts and behaviours that maintain insomnia. Its main components are:

Stimulus control: go to bed only when sleepy, use the bed only for sleep and intimacy, get up if you cannot sleep within about 20 minutes and return when sleepy, and keep a fixed wake time.
Sleep restriction: temporarily limit time in bed to match your actual sleep time, then gradually extend it as sleep becomes more efficient.
Cognitive therapy: identify and challenge unhelpful beliefs such as “I must get 8 hours or I will be ill”.
Relaxation and worry management: breathing, muscle relaxation and scheduled “worry time”.
Sleep education and relapse-prevention planning.

CBT-I is effective in about 70–80% of people, has lasting effects and can be delivered face to face, in groups, by telephone or via validated digital programmes.

Sleep habits that help

Keep a regular sleep and wake time every day, including weekends.
Get daylight in the morning and be physically active during the day, finishing intense exercise 2–3 hours before bed.
Limit caffeine after midday and avoid nicotine and alcohol near bedtime.
Eat a lighter evening meal and avoid going to bed hungry or overly full.
Make the bedroom dark, quiet, cool and comfortable.
Wind down for 30–60 minutes before bed and keep screens out of the bedroom.
Limit naps to under 30 minutes, early in the afternoon.
Do not watch the clock.

Medicines and supplements

Medication can help in the short term, but it is not a long-term solution. Options include short courses of benzodiazepine receptor agonists (“Z-drugs” and benzodiazepines), low-dose doxepin, orexin receptor antagonists and, in some situations, sedating antidepressants. They carry risks, including next-day drowsiness, falls, memory effects and dependence, and should be used at the lowest dose for the shortest time, with medical supervision. Melatonin helps circadian rhythm problems and jet lag, with a small effect on typical insomnia. Over-the-counter antihistamine sleep aids lose effect quickly and can cause daytime sedation, confusion and urinary retention in older adults. Herbal products such as valerian have inconsistent evidence.

When your mind will not switch off

Racing thoughts at bedtime are one of the most common features. Writing a to-do list or “worry diary” earlier in the evening, practising slow breathing or progressive muscle relaxation, using mindfulness or guided audio, and avoiding problem-solving in bed all help. If you lie awake worrying about not sleeping, remember that one poor night is not harmful, and trying hard to sleep makes it harder. See no puedo dormir (Spanish).

Insomnia in older adults, pregnancy and menopause

Older adults sleep lighter and wake more often; avoid long naps, stay active and review medicines. Sedatives increase the risk of falls and confusion.
Pregnancy: discomfort, reflux, frequent urination and anxiety disrupt sleep; focus on habits, side-lying positions and CBT-I; ask the doctor before any medicine.
Menopause: hot flashes and night sweats can fragment sleep; treat the cause and use CBT-I; discuss options with your doctor.

When to see a doctor

Insomnia lasting more than 3–4 weeks or affecting daytime functioning.
Snoring with breathing pauses or severe sleepiness.
Persistent low mood, anxiety or thoughts of self-harm.
Reliance on alcohol or sleeping tablets.
Unusual movements or sensations in the legs at night.
Insomnia that began after a new medicine.

Three common situations

Poor sleep for a week during exam stress: keep routines, limit caffeine and use relaxation; it usually resolves.

Lying awake for hours each night for six months: a good candidate for CBT-I.

Waking at 3 a.m. and unable to return to sleep: avoid the clock, get up if awake for over 20 minutes and assess mood and alcohol use.

Key points to remember

Insomnia is common and treatable. CBT-I is the recommended first-line treatment, with healthy sleep habits and treatment of contributing conditions. Use medication sparingly. In our psychology consultation we offer evidence-based support for sleep problems.

This guide is for general information and does not replace an assessment by a qualified health professional.

Questions about insomnia

These answers are general information and do not replace an examination or individual medical advice.

What is the best treatment for insomnia?

Cognitive behavioural therapy for insomnia (CBT-I) is the recommended first-line treatment.

How many hours of sleep do I need?

Most adults need 7–9 hours, with individual variation.

Is melatonin effective for insomnia?

It has a small effect in typical insomnia and works best for jet lag or delayed sleep phase.

Are sleeping pills safe?

They can help in the short term but have risks, including dependence and next-day impairment. Use them only as prescribed.

How long does CBT-I take?

Typically 4–8 sessions, with improvement often seen within a few weeks.

Can insomnia cause health problems?

Chronic insomnia is linked to depression, anxiety, accidents and cardiovascular risk, which is why treatment matters.

Sources

This guide is for general information and does not replace medical advice. How a problem is diagnosed and treated depends on your examination and medical history. If you think you have an emergency, contact your local emergency services.