People with narcolepsy are struck by an abrupt, insatiable urge to sleep during the day. Type 1 narcolepsy is also accompanied by a symptom called cataplexy, which causes muscles to suddenly weaken.
Research indicates that type 1 narcolepsy may be linked to immune system dysfunction. Molecules called orexins, which are used by neurons within the hypothalamus, are much lower in cerebrospinal fluid samples taken from people with type 1 narcolepsy. It is theorized that the immune system may be mistakenly attacking either the neurons or orexin molecules, which leads to excessive daytime sleepiness.
As for symptoms, narcolepsy is linked to four distinct health effects, but most people with the condition do not experience all of them. As the primary symptom of type 1, cataplexy causes mild to severe muscle weakness, which can affect muscles all over the body (some people only experience weakness on one side, however). Other symptoms of narcolepsy include:
Narcolepsy can also cause forgetfulness, strange outbursts, and automatic movements (which occur while a person’s sleeping).
Type 1 narcolepsy is not usually hazardous to your health, but repeated bouts of sleepiness during the day can cause problems at work and at home. Additionally, cataplexy can lead to serious injuries if a person loses full control of their muscles in certain situations, such as descending the stairs or driving a vehicle.
You will most likely undergo a sleep study to accurately diagnose narcolepsy. You may also undergo a spinal tap to test the level of orexins in your body. Because cataplexy can mimic other disorders that affect the muscles, your doctor may perform additional tests to rule them out.
While type 1 narcolepsy cannot be cured, it can be managed with medication. Most people initially receive so-called wakefulness drugs, which affect the nervous system to combat daytime sleepiness. Doctors can also prescribe stimulants, such as amphetamines.
When it comes to cataplexy, sodium oxybate acts upon certain receptors to improve the sleep cycle at night (people with narcolepsy skip the first three sleep stages and immediately experience REM sleep as soon as they nod off). Other narcolepsy treatments include antidepressants and histamine receptor antagonists, which also boost wakefulness.