Sleep Disorders

Insomnia, sleep apnea and narcolepsy

By Sarah Leavitt, Medical Research EditorLast modified: March 07, 2011

Sleep Disorders

Sleep disorders are neurological problems that can range from occasional disrupted sleep patterns to insomnia over a period of months. There are over 60 identified forms of sleep disorder categorized in three ways:


  • Lack of sleep
  • Excess sleep
  • Disrupted sleep


Lack of sleep

To function efficiently doctors advise 8 hours of uninterrupted sleep nightly. Sleep disorders such as insomnia cause lack of sleep over a prolonged period. Continuous lack of sleep can cause mental and physical health problems. 


Insomnia is the neurological disorder of lack of sleep. Symptoms of insomnia include:


  • Difficulty falling asleep
  • Waking at intervals throughout the night and being unable to return to sleep
  • Waking exceptionally early

It is normal for people to experience insomnia to some degree at various intervals. Stress, worry, lifestyle changes and medications can all trigger insomniac periods. If the problems sleeping continue for more than a week, patients should seek medical advice.


Excess Sleep

Narcoplepsy is a sleep disorder where the sufferer is unable to satisfy the body's need for sleep at night. Sufferers of narcolepsy will fall asleep suddenly during the day for anything between 1 minute and one hour intervals. The fall into sleep will be sudden - narcoleptics are often engaged in an activity when they begin to sleep. Narcolepsy is generally a genetically inherited condition but may also occur following brain injury. 


Disrupted Sleep

There are many causes of sleep disruption and often the cause of interrupted sleep is easily identified as stress, worry, excess tiredness or illness. Medical conditions and sleep disorders can cause continuous periods of interrupted sleep. Below are the most common reasons for disrupted sleep and the most common forms of sleep disorders:


  • Sleep apnea - There are two forms of sleep apnea - obstructive sleep apea and central sleep apnea.

Obstructive sleep apnea is common. The disrupted sleep is caused by a blockage in the throat that disrupts breathing and wakes up the sufferer. Common reasons for obstructive sleep apnea are obesity and excess alcohol consumption. 


Central sleep apnea is more serious. The disruptions to sleep occur due to the signals telling the body to breathe do not pass from the brain. This causes a sufferer to stop breathing periodically and wake up to inhale deeply. 


Both forms of sleep apnea are categorized by snoring as the sufferer struggles to breathe.


  • Restless Leg Syndrome - People with this condition wake during the night because of feelings of pins-and-needles and tingling in the legs

  • Similar to RLS is Periodic Limb Movement (PLM). This causes the limbs to jerk involuntarily while the sufferer is asleep causing them to jerk awake suddenly. 

There are many ways to treat sleep disorders from medication to behavioural sleep therapy. For more information on controlling a sleep disorder, contact a neurologist who will determine the cause and type of sleeping disorder in order to provide the correct treatment. 

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This article was written by the medical research team at does not intend for any of the information on this site to be regarded as medical advice - it is meant as a starting point for understanding treatment details and options before contacting a registered, licensed doctor. We advise all patients to seek medical advice from a doctor.
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