Canít stay awake? Go weak at the knees when you laugh? Sleepy all the time? Most of us feel like this some of the time, but if this is a constant daily feature of your life which you have noticed since your teens then, whilst rare, narcolepsy is a consideration. Read on
Narcolepsy is a type of sleep disorder. It is rarer than other forms of sleep disorder, which cause excessive sleepiness, affecting roughly 3 per 10,000 people. Sleep apnoea is 100 times commoner that narcolepsy. However, narcolepsy is more relevant to young people as symptoms are most likely to start in the teenage years, whereas the other sleep disorders Ė sleep apnoea and PLMS (periodic limb movement syndrome) are commoner in middle age.
It is a neurological disorder typified by sudden and irresistible sleep attacks in the daytime. Of course we have all been subject to that during certain lessons, lectures and seminars, but these attacks may occur anywhere and are accompanied by other symptoms including
- hallucinations (vivid waking dreams) as you fall asleep and when you wake up
- short-lived sleep paralysis, again at sleep onset or awakening which can be accompanied by hallucinations
- cataplexy. This is when short-lived episodes of muscular weakness occur at times of intense emotion, so the muscles in the legs may give way when you laugh or cry
- fragmented nocturnal sleep
Daytime sleep attacks associated with cataplexy make a clinical diagnosis easy, however, this combination only occurs in a small number of sufferers. Laboratory testing which includes analysis of nocturnal sleep patterns, brain activity, muscle tone and eye movements is usually necessary. These tests allow assessment of the degree of sleepiness and identification of REM sleep (dreaming sleep) during daytime naps.
A blood test may also be necessary.
The symptoms of narcolepsy can be dramatically improved even though there is no cure. Stimulant drugs may be prescribed for excessive daytime sleepiness. Certain tricyclic antidepressant drugs, such as clomipramine can improve cataplexy. These reduce the tendency to REM sleep. Scheduling daytime naps can also help to improve levels of alertness.
This article published on
12 December 2005
Next review date 01/12/2013