Narcolepsy

**Narcolepsy** is a sleep disorder. It happens when the nervous system does not work properly or if there is a hormonal imbalance. Mental health issues like depression and ADHD, and drug use can cause narcolepsy. This condition is categorised as excessive daytime sleepiness. Very often, a person with the condition does not sleep well at night, and during the day they fall asleep uncontrollably.

Narcolepsy affects the way the nerves work. It is not a mental illness, or caused by psychological problems[<sup>source?</sup>]. It is estimated that between 25 and 50 people, per 100,000 suffer from narcolepsy. Very few cases are reported.

The first description was given in 1877. Jean-Baptiste Gélineau, a military doctor, first used the name narcolepsy in 1880.

In certain countries, people diagnosed with narcolepsy may not drive a car.

## Forms of narcolepsy

There are two different forms of narcolepsy. There is NT1 which frequently involves cataplexy, the sudden and brief loss of muscle tone, where the individual becomes unconscious. This can be triggered by strong emotions like laughter, anger, and surprise.

NT2 shares many symptoms with NT1 however does not involve cataplexy.

## Symptoms

Things that people with narcolepsy may experience:
- Excessive Daytime Sleepiness: Being very tired during the day even after a full night of sleep. This is the most common symptom of narcolepsy.
- Cataplexy: Suddenly having a muscle fail them. This can range from a slight weakness, and problems speaking clearly, to completely collapsing.
- Sleep paralysis: When waking up, people are paralysed  (unable to move) for a certain time. The paralysis eventually goes away.
- Hallucinations, while falling asleep or waking up.
- Automatic behaviour: People continue doing things while they are asleep. Later on they do not remember.

Hallucinations, sleep paralysis, and automatic behaviour can also occur in people who are not narcoleptics. This usually happens when people are very tired, and have not slept for a long time.

## Causes

Narcolepsy with cataplexy (NC) is caused by the loss of hypocretin neurons. Hypocretin is a chemical in the brain that alerts the brain when to wake up and regulates sleep. Quite a few sufferers also have another family member with the disease. This may point to the fact that some of the things that cause the disease may be passed from the parents to the children through genes.

## Treatments

There are certain drugs that can treat the effects of narcolepsy. In most cases special kinds of stimulants are used such as methylphenidate, modafinil, dextroamphetamine sulfate, methamphetamine, and amphetamine, a dopamine/norepinephrine reuptake inhibitor to reduce daytime sleepiness . General stimulants, like coffee, usually do not help. Some strategies for treatment do not rely on drugs:
- Adapting the behaviour to avoid situations that trigger daytime sleep; this is generally known as Coping. It also involves changing the daytime rhythm to accommodate the sleeping phases
- Sleep hygiene

## Other websites

- Narcolepsy Fact Sheet: National Institute of Neurological Disorders and Stroke
- Narcolepsy Network
- http://www.narcolepsy.org.uk/index_html
- Read about Narcolepsy in the Sleeptionary
- What is Narcolepsy
- Narcolepsy: Symptoms, Causes, Diagnosis, and Treatment
- Harvard Division of Sleep Medicine Module on Narcolepsy