Written by: 
Dr Roger Henderson

Insomnia is defined as a disturbance of a normal sleep pattern, such as the inability to fall asleep, or to stay asleep for long enough to feel refreshed in the morning.

Different people require different amounts of sleep, with most adults usually needing seven to eight hours each night. From about the age of 40, adults tend to need less sleep overall as they age, and they also take longer to fall asleep. Insomnia is therefore more frequent with increasing age, and occurs most often in people over the age of 65.

Insomnia is a common problem that can be difficult to overcome, but it helps to understand the causes and the stages of normal sleep, as well as your treatment options.


For someone to be diagnosed with significant insomnia, a number of key factors have to be present:

  • Symptoms lasting for more than one month
  • Difficulty in getting to sleep, or staying asleep
  • Significant distress caused by its effects
  • Impaired daytime and social functioning - lack of sleep causes irritability, anxiety and depression.

Doctors divide insomnia into two main groups, called 'primary' and 'secondary' insomnia. Primary insomnia occurs when someone has troublesome sleep patterns that are not directly explained by another underlying problem. This type of insomnia accounts for 10 per cent of cases.

In contrast, secondary insomnia is far more common and results from an underlying physical or mental health problem, or from external influences such as medication, alcohol, noise or lifestyle factors.


There is no one single overall cause of insomnia, but there are many common triggers found in the vast majority of sufferers. These include:

  • Physical causes, such as pain, asthma, hot flushes, neurological problems
  • Psychological causes, for instance, stressRelating to injury or concern., anxiety, relationship problems
  • Medication, which could include asthma treatments, antidepressants, thyroid supplements, appetite suppressants
  • Environmental, for example, noise, being too hot or cold, an uncomfortable bed
  • Lifestyle, including eating late, smoking, alcohol, exercising before bedtime.

Most cases of insomnia do not rely on any specific test for the diagnosisThe process of determining which condition a patient may have. to be made; doctors generally use a detailed history and a careful clinical examination to confirm it. Your doctor may try to classify your insomnia in one of three ways:

  • Transient: lasting a few nights only
  • Short-term: lasting more than three nights but less than three weeks
  • Long-term, or chronicA disease of long duration generally involving slow changes.: occurring most nights and lasting more than three weeks.

Tip: If the cause of your insomnia is not immediately apparent, you may be asked to keep a sleep diary in which you can record when you went to sleep, and for how long. Sleep diaries provide a useful assessment of the impact insomnia has on an individual's quality of normal daily life

Very rarely, a specialised test known as a polysomnograph may be needed. During this test, electrodes are placed on the head and body, and the electrical activity of the brain is recorded during sleep, along with other elements such as breathing, oxygen levels and heart rate. Such tests are more normally used in the diagnosisThe process of determining which condition a patient may have. of obstructive sleep apnoea, a common cause of poor sleep and daytime sleepiness.

What is normal sleep?

Normal sleep consists of five successive stages that, when taken together, make up what is known as the sleep cycle. Stages 1 and 2 are called 'light sleep' and stages 3 and 4 'deep sleep'.

  • Stage 1: light sleep - when you are half-awake and half-asleep
  • Stage 2: the onset of sleep, where you progressively disengage from your surroundings
  • Stage 3: deep sleep - the restorative phase of sleep
  • Stage 4: deeper sleep, where it becomes more difficult to wake up
  • Stage 5: REM (rapid eye movement) sleep; a phase that usually begins about 90 minutes after going to sleep and a crucial one if you are to remain alert during the day. With each successive sleep cycle throughout the night, the duration of this cycle increases.

With age, there is a gradual deterioration in the amount of deep refreshing sleep that occurs. This may partly explain why insomnia appears to occur increasingly with advancing years.

As part of this natural sleep cycle, the hormoneA substance produced by a gland in one part of the body and carried by the blood to the organs or tissues where it has an effect. melatonin appears to play a critical role. Produced by the pineal glandAn organ with the ability to make and secrete certain fluids. in the brain, its production is stimulated by darkness and helps promote the onset of sleep as well as progression into deeper REM sleep. Studies show that there is a relationship between increasing age, reduced production of melatonin and a rise in insomnia.


The first step in treating insomnia is to have any underlying cause diagnosed. For example, if you have depression and this is causing your insomnia, treating this will often remove the insomnia. In the first instance, non-drug treatment is the preferred course of action.


Counselling can be very helpful if insomnia is caused by stressful life events or anxiety. Cognitive behavioural therapy (CBT) may be part of this treatment, as this has been shown to be of use in altering behaviour and thinking patterns; keeping a sleep diary may also help.

Lifestyle advice

For many people, lifestyle advice is key and often all that is needed to reduce or stop insomnia from continuing. Common measures can often be successful, including:

  • Restricting caffeine, nicotineAn addictive substance found in tobacco and nicotine replacement therapies. and alcohol
  • Having regular exercise
  • Maintaining a good sleeping environment
  • Keeping regular times for sleeping and waking.

Other advice includes not using the weekend to catch up on sleep and not watching television in the bedroom. Having sex before sleeping may help, as orgasm often helps promote restful sleep.

If it takes you longer than half an hour to get to sleep, don't lie in bed worrying about not sleeping. Instead, get up and go to another room for a short time to undertake another activity, such as reading, before returning to bed and trying to get to sleep again.

Sleeping tablets

Although often requested by insomnia sufferers, these are not the preferred first choice of treatment by doctors. They are usually considered only if the person has very severe insomnia, and only in the short term.

Doctors are reluctant to prescribe sleeping tablets as they feel they do not treat the cause and there can be a very real risk that you may become dependent on them if you use them for lengthy periods of time.

Available only on prescription, the two types of sleeping tablets prescribed are the short-acting benzodiazepines (diazepam and loprazalam, for example) and the newer hypnotics, which are sometimes called the 'Z' drugs (zopiclone and zolpidem, for example).

Whatever the choice of drug given, the smallest effective dose possible should be taken for the shortest length of time, usually for a week at most. In some cases your doctor may recommend that you take them two or three nights a week rather than every night. Side-effects include drowsiness the following day, so care must always be taken if driving that day.

Tip: Never be tempted to use other types of medication such as antidepressants, antipsychotics or barbiturates to treat insomnia. Not only are they not designed for this purpose, but these are powerful drugs that potentially have significant side-effects if used incorrectly


Melatonin is used by jet-lag sufferers around the world and may also help insomnia sufferers in the short term. Preparations that contain melatonin are available in some countries.

Natural remedies

There is some evidence that the herb valerian can be effective in treating insomnia, although not all studies have shown a benefit. Some small studies suggest that aromatherapy treatment with lavender oil may improve sleep quality, although more research is needed to confirm this.

A traditional remedy is camomile tea, which is said to have calming effects and to induce sleep; some animal studies show it has a sedative effect, but there is as yet little human research to confirm these benefits.