Insomnia is difficulty getting to sleep or staying asleep for long enough to feel refreshed the next morning.

This happens despite having enough opportunity to sleep. 

The most common problem in young people with insomnia is difficulty falling asleep (sleep-onset insomnia). An insomniac may also experience:

  • Waking in the night (most common in older people).
  • Not feeling refreshed after sleep and not being able to function normally during the day, feeling irritable and tired and finding it difficult to concentrate.
  • Waking when you have been disturbed from sleep by pain or noise.
  • Waking early in the morning (the least common type of sleep disturbance).

Nearly everyone has problems sleeping at some point in their life and it is thought that a third of people in the UK have bouts of insomnia. Insomnia appears to be more common in women and more likely to occur with age.

There are a number of possible causes for insomnia, such as anxiety, a disrupted sleeping environment, or an underlying physical condition or mental health problem (see Causes).

How long does insomnia last?

Insomnia can last for days, months or even years. It can be split into:

  • short-term insomnia, which lasts for one to four weeks, and
  • long-term (or persistent) insomnia, which lasts for four weeks or longer.

How much sleep should you get?

Every individual is different, so it is hard to define what normal sleep is for you. Factors influencing the amount of sleep you need include your age, lifestyle, diet and environment.

For example, newborn babies can sleep for 16 hours a day, while school-age children need an average of 10 hours sleep.

Most healthy adults sleep for an average of seven to nine hours a night. As you get older, it is normal to need less sleep. Most people over 70 need less than six hours sleep a night, and they tend to be light sleepers.


Pain is an unpleasant physical or emotional feeling that your body produces as a warning sign that it has been damaged.


Chronic usually means a condition that continues for a long time or keeps coming back.


Depression is when you have feelings of extreme sadness, despair or inadequacy that last for a long time.
Last updated: 04 October 2011

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