Narcolepsy
Narcolepsy is a chronic neurological disorder of sleep-wake regulation. Its central symptom is recurrent irresistible sleepiness or unintended daytime sleep episodes.
Unstable boundaries between wakefulness and REM sleep
In type 1 narcolepsy, cataplexy—sudden loss of muscle tone with awareness preserved—or documented orexin deficiency is present. Type 2 lacks cataplexy and has normal or unmeasured orexin with the appropriate objective sleep pattern.
Sleep paralysis and vivid experiences while falling asleep or waking are common but not required and can occur without narcolepsy. Short naps may briefly restore alertness, while night sleep can remain fragmented. Symptoms and a genetic test alone do not establish the diagnosis.
Specialist diagnosis
- Irresistible sleepiness or daytime sleep occurs at least three times a week for three months.
- Diagnosis also requires cataplexy, documented low cerebrospinal-fluid orexin or a defined REM-onset pattern on overnight polysomnography and the multiple sleep latency test.
- Insufficient sleep, shift work, apnoea, other hypersomnolence disorders, medicines and substances are excluded before testing is interpreted.
- Children may appear irritable or hyperactive rather than simply reporting sleepiness, so school and family observations can be important.
Treatment and daily planning
A regular schedule, sufficient night sleep and planned short naps are combined with specialist treatment. Wake-promoting medicines and treatments for cataplexy or fragmented sleep are selected according to age, pregnancy, cardiovascular health and other individual factors.
School or workplace adjustments may include a safe place for planned sleep, written instructions and flexible breaks. Safety planning covers driving, swimming, heights, cooking and infant care, while psychological support can address stigma and the restrictions of a chronic condition.
When to seek help
Seek assessment for unintended sleep despite adequate rest, brief muscle weakness after laughter or emotion, or sleep paralysis and vivid sleep-transition experiences accompanied by persistent daytime sleepiness. Record sleep timing, episodes and medicines before the appointment.