Narcolepsy overview

Understanding Narcolepsy

A complex, chronic
neurological disorder1-3

  • Underrecognized and underdiagnosed2
  • Approximately 50% of patients may be undiagnosed2
  • Symptoms generally start during young adulthood, most commonly before 25 years of age2,3
  • Symptoms are often attributed to other disorders, leading to potential for misdiagnosis4,5
  • Many years may pass before a definitive diagnosis is made6,7

Excessive Daytime Sleepiness (EDS) in Narcolepsy

EDS is primarily characterized by the inability to stay awake and alert during the day3

  • EDS is an essential feature of the diagnostic criteria (ICSD-3) for narcolepsy3

EDS can be measured using the Epworth Sleepiness Scale (ESS)8,9

  • The ESS is a subjective scale that has been validated to quantify the degree of daytime sleepiness8,9
  • The ESS assesses the propensity to doze or fall asleep in 8 common daily activities8,9

To assess the level of daytime sleepiness using the ESS, have your patient fill out a symptom checker such as the one below. Have your patient rate how likely he or she would be to doze or fall asleep in the everyday situations described using the following scale .

  • 0 = Would never doze
  • 1 = Slight chance of dozing
  • 2 = Moderate chance of dozing
  • 3 = High chance of dozing
Chance of dozing

Sitting and reading

Watching television

Sitting inactive in a public place (eg, a theater or a meeting)

As a passenger in a car for an hour without a break

Lying down to rest in the afternoon when circumstances permit

Sitting and talking to someone

Sitting quietly after a lunch without alcohol

In a car, while stopped for a few minutes in traffic

Total Score : 0

Interpreting ESS scores8,9: ESS 0–10 = Normal; ESS >10 = EDS; ESS ≥16 = High levels of EDS

Cataplexy in

Cataplexy is characterized by the sudden, generally brief loss of muscle tone with retained consciousness3

Cataplexy is the most specific symptom of narcolepsy3,10

Common features include:
  • Attacks triggered by strong emotions, such as laughing, joking, anger3,11
  • More commonly partial or localized10,12
  • Wide variations in frequency3
To help identify cataplexy:
  • Ask patients if they’ve experienced symptoms10
  • Verify whether patients are taking certain medications that may suppress cataplexy (eg, antidepressants)10,12
  • Ask patients if they avoid situations that may trigger cataplexy10