What causes insomnia?

Short term and long term insomnia

Most people have a few bad nights after a stressful event. This usually settles on its own within a few weeks.

Insomnia is called chronic when trouble falling asleep, staying asleep or waking too early happens at least three nights a week for three months or more, and affects how you feel during the day.

Common causes

Stress and worry are the most common triggers. A busy mind at night keeps the body alert when it should be winding down.

Irregular sleep times, shift work, long naps, caffeine late in the day, alcohol and screens in bed can all weaken the body's natural sleep rhythm.

Health problems such as pain, breathing problems at night, menopause symptoms, anxiety and low mood can disturb sleep. Some medicines can too.

Why it keeps going

Insomnia often outlasts its original cause. After weeks of poor sleep, the bed itself can become linked with being awake and frustrated. Trying harder to sleep then makes it harder.

This is why approaches that retrain sleep habits, such as CBT-I, are recommended as the first step for long term insomnia.

When to speak to a clinician

Speak to your GP or a clinician if poor sleep has lasted more than three months, affects your work or mood, or if you snore loudly, stop breathing in your sleep or have restless legs.

If you are having thoughts of harming yourself, call 999 or NHS 111, or contact Samaritans on 116 123.