Narcolepsy

About Narcolepsy

Narcolepsy is a chronic neurological sleep disorder affecting approximately 1 in 2,000 people. Type 1 narcolepsy with cataplexy involves loss of hypocretin orexin producing neurons in the hypothalamus, resulting in undetectable cerebrospinal fluid hypocretin levels. Type 2 narcolepsy without cataplexy has normal hypocretin. The core symptom is excessive daytime sleepiness EDS, an irresistible need to sleep that can occur at any time, often in inappropriate settings meetings, class, driving. Sleep attacks last from seconds to minutes. Cataplexy, unique to type 1, is sudden bilateral loss of muscle tone triggered by strong emotions laughter, anger, surprise, ranging from mild facial sagging to complete collapse while remaining conscious. Sleep paralysis, inability to move or speak while falling asleep or waking up, lasting seconds to minutes, can be terrifying. Hypnagogic at sleep onset or hypnopompic at waking hallucinations are vivid, often frightening, dream like experiences. The tetrad of EDS, cataplexy, sleep paralysis, and hypnagogic hallucinations characterizes classic narcolepsy. Diagnosis involves polysomnography showing sleep onset REM periods SOREMPs within 15 minutes, and the Multiple Sleep Latency Test MSLT showing mean sleep latency below 8 minutes with 2 or more SOREMPs. CSF hypocretin 1 below 110 pg mL confirms type 1. Treatment manages symptoms but does not cure. Wakefulness promoting agents modafinil Provigil, armodafinil Nuvigil are first line for EDS. Solriamfetol Sunosi and pitolisant Wakix are newer options. Sodium oxybate Xyrem treats both EDS and cataplexy but has abuse potential. Antidepressants venlafaxine, fluoxetine, clomipramine suppress cataplexy. Scheduled naps help.