Tragic to have, funny to watch, narcolepsy is a neurological condition that causes the brain to send signals out about when to be awake and when to be asleep at completely inappropriate times. In minor instances a sufferer will find themselves getting sleepy while watching a cricket final. Severe cases can see the narcoleptic falling asleep while standing, sitting, in conversation or while pursuing some other physical activity. In some cases physical harm may result due to being in control of a motor vehicle at the time, or nodding off at the wrong moment during sex.

A particularly notable aspect of narcolepsy as a neurological disorder is the tendency for sufferers to enter states of REM sleep¹ very quickly on sleeping. Symptoms of narcolepsy may also be closely associated with REM sleep.

Narcolepsy is a rare condition which has strong genetic associations with nearly all sufferers having the HLA-DR2 gene. An associated condition is cataplexy, where there is sudden loss of tone in the lower limbs with preservation of consciousness. Though Narcolepsy is a genetic disorder, you should not start to worry if your father dozes in front of the television and pretends to have been awake when the channel is changed. Everyone's father does that. Narcoleptics are more typically youths, or young adults.

Symptoms

• Hypnagogic² or hypnopompic³ sleep paralysis - Being unable to talk or move for about a minute when falling asleep or waking.

• Hypnagogic or hypnopompic hallucinations - Vivid and frightening dreams and sounds when falling asleep or on waking. These may also be caused by any Vindaloo worth the name.

• Cataplexy - A sudden loss of muscle control. This may range from a slight weakness to complete collapse. The symptom is frequently triggered by intense emotional response. For maximum hilarity in inducing this symptom the sufferer should be either running, eating or a chicken. If you find a chicken that suffers chronic cataplexy, spend hours creeping up behind it and saying, 'BOO!'.

Narcolepsy should not be confused with Sleep Apnoea⁴, its more sinister relative.

Treatment

Most cases of narcolepsy are treated with medication. Stimulants are prescribed, such as Dexedrine, Ritalin and Cylert. Methamphetamines have also been prescribed, although substantially less frequently. A newer treatment for narcolepsy is modafinil (trade name Provigil), again this is a central nervous system stimulant which may cause dependence.