diagnostic criteria

Last reviewed 01/2018

There are two approaches to diagnosis:

  • both of the following:

    • almost daily daytime sleep episodes for 3 months
    • cataplexy

  • all four of the following:

    • excessive daytime sleepiness or sudden muscle weakness
    • any of:
      • sleep paralysis
      • hypnagogic hallucinations
      • automatic behaviour
      • disrupted nocturnal sleep episodes
    • any of the following polysomnographic features:
    • nocturnal sleep latency less than 10 min
      • nocturnal REM sleep latency less than 20 min
      • mean sleep latency less than 8 min on the multiple sleep latency test (MSLT)
      • two or more sleep onset REM periods during MSLT
    • exclusion of medical or psychiatric causation