In narcolepsy, the loss of hypocretin (orexin) neurons leads to reduced or inconsistent activation of histamine and other wake-promoting neurons, ultimately resulting in sleep-wake state instability2,3
- EDS is caused by reduced or inconsistent activation of histamine and other wake-promoting neurons, leading to unstable wakefulness throughout the day2,3
- May lead to periodic activation of non-REM sleep–promoting neurons and REM sleep–promoting neurons, further destabilizing wakefulness and exacerbating EDS3-5
- Cataplexy is caused by the sudden activation of REM sleep–promoting neurons during the day, allowing elements of REM sleep (i.e., muscle atonia) to intrude into wakefulness and destabilize muscle tone2,3,6
Did you know?
Approximately 165,000 people in the United States have narcolepsy2,7
Narcolepsy is estimated to be the second most common cause of excessive daytime sleepiness (EDS) seen in US sleep centers8,9,*
*Based on a 2-month, prospective, point-prevalence survey of 3970 patients evaluated at 19 accredited regional sleep centers in the US.8