narcolepsy

• related: Psychiatry

• Sx include: fragmented sleep, hypnagogic hallucinations, sudden onset of sleep during day
• Population: teen to late 20s

• Diagnosed by sleep study/polysomnography
  • multiple spontaneous awakenings
  • reduced sleep efficiency (total sleep time divided by total recording time)
  • reduced latency of rapid eye movement (REM) sleep.
• Polysomnography can also exclude other causes of EDS (excessive day time sleepiness) (eg, sleep apnea).

• goal: reduced excessive day time sleepiness
• modafinil: novel stimulant, less addictive, first line
• older stimulants: methylphenidate, amphetamines
  • effective but addictive
  • bad side effects
• nonpharmacologic:
  • taking scheduled naps
  • good sleep hygiene

• sudden onset of muscle weakness
• triggers: intense emotional episodes (eg, anger, laughing, surprise)
• occurs in roughly 70% of patients with narcolepsy.
• Treatment: stimulants, nonpharmacologic
• can be treated with a serotonin-norepinephrine reuptake inhibitor (eg, venlafaxine) or selective serotonin reuptake inhibitor, and a tricyclic antidepressant can also be considered.
• Sodium oxybate (the salt form of gamma-hydroxybutyrate) can improve nocturnal sleep, relieve excessive daytime sleepiness and has anti-cataplectic properties; however, it is rarely used due to abuse potential and restrictive regulations.