National Sleep Foundation

Chapter 4: Primary Hypersomnias

Kleine-Levin Syndrome Overview

Kleine-Levin Syndrome (KLS) is the best-defined recurrent hypersomnia and is characterized by recurrent episodes of hypersomnia in which patients sleep for 12-24 hours a day. Patients with KLS, which is also called “Sleeping Beauty disease,” may sleep for days, weeks, or months, waking only to eat and/or use the bathroom.59

This hypersomnia is also associated with mood disturbances (e.g., irritability, aggression, compulsivity) and cognition (e.g., de-realization, confusion, hallucinations, depression), compulsive eating, and hyper-sexuality.60


  1. Arnulf I, Zeitzer JM, File J, Farber N, Mignot E, “Kleine-Levine Syndrome: a systematic review of 186 cases in the literature, Brain 2005, vol. 128 no 12, pp. 2763 - 2776.  DOI:
  2. Gadoth N, Kesler A, Vainstein G, Peled R, Lavie P. Clinical and polysomnographic characteristics of 34 patients with l-Levin syndrome. J Sleep Res. 2001;10:337-341.