NARCOLEPSY

What is It?

Narcolepsy is a malfunction of the sleep/wake regulating system in the brain of unknown origin. Its most common manifestation is an irresistible tendency to fall asleep, even in unlikely circumstances such as in the middle of a conversation or at a meal.

The other conspicuous symptom is a sudden loss of muscular control triggered by amusement, anger or excitement which is called cataplexy. The effects of cataplexy range from dropping of the jaw and slumping of the head, to buckling of the legs and even collapse of the whole body; they last for a few seconds or up to many minutes.

Other symptoms of Narcolepsy are:

• temporary paralysis on falling asleep or awakening, often accompanied by hallucinatory or nightmarish experiences;
• moments (but sometimes extended periods) of trance-like behaviour in which routine activities are continued on ?auto-pilot?;
• interruption of night-time sleep by waking periods, marked by quickening of the heartbeat, over-alertness, hot flushes, agitation, and an intense craving for sweets.

Narcolepsy usually begins in adolescence but instances of onset earlier, or as late as middle age, are on record. The type and severity of symptoms vary from person to person and may either improve or worsen with time.

The reputed incidence of narcolepsy in the population ranges from two in 10,000 in Germany and North America, to 16 in 10,000 in Japan.

An inheritable factor has been identified which can increase the likelihood of developing narcolepsy by up to 10 times in persons with the factor compared with those without it.