Kleine-Levin Syndrome : A Rare Sleeping Disorder

August 5, 2013

What is Kleine-Levin Syndrome?
Kleine-Levin Syndrome (KLS), also known as “Sleeping Beauty” syndrome, is a rare neurological disorder characterised by recurrent bouts of hypersomnolence (excessive sleeping) along with cognitive and behavioural problems during wakefulness. The exact prevalence of KLS is unknown but is estimated to be around 1 in a million. Among those afflicted, 70% are male.

Patients sleep between 12 and 24 hours a day waking only to eat and use the toilet. During wakefulness patients experience symptoms including disorientation, confusion, hallucinations, irritability, lethargy and apathy. They are not able to care for themselves or attend school.

KLS usually begins during adolescence and symptoms appears in “episodes”, occurring between 2 and 12 times per year. When an episode occurs it can last for a few days or up to several months. Once an episode ends, patients generally have no recollection of their experience. The symptoms can reappear with little or no warning.

In between episodes, patients diagnosed with KLS can show perfect health with no evidence of behavioural or physical dysfunction. They usually lead normal lives with regular sleep patterns. As the patient ages, the episodes become less frequent and eventually disappear. However in some cases, the condition has been reported in patient’s in their 40s and 50s. The list of symptoms includes:

(1) Hypersomnia or excessive sleep: This is the primary symptom of KLS and is a necessary condition for diagnosis. Patients spend between 12 and 24 hours asleep and are difficult to arouse from sleep.

(2) Cognitive impairment: Patients experience confusion, diminished comprehension, poor concentration, memory problems and difficulty in communicating. Speech impairments are also common such as; monosyllabic, slurred and childish speech.

(3) Altered perceptions: most patients report feeling ‘disconnected’ with the real world in some way during an episode, as if their surroundings seemed wrong, distorted, as in a dream. In addition some patients experience auditory and visual hallucinations.

(4) Compulsive eating (hyperphagia): three quarters of KLS patients experience eating disorders during episodes. They have powerful cravings for foods they normally would not eat such as sweets or junk foods.

(5) Hypersexuality : some patients, usually males exhibit heightened sexual urges. This hypersexual behaviour includes excessive masturbation, promiscuity, inappropriate sexual advances, and other risqué behavior.

Other symptoms: these include migraine headaches; hypersensitivity to light and noise; anxiety; irritability. Many KLS patients also show autonomic symptoms like abnormal body temperature, changes in heart rate and blood pressure and flu-like symptoms.

What Causes KLS?
As of yet, the medical community doesn’t know what causes KLS but the pathology of the disease suggests a malfunction in the hypothalamus and thalamus. These are regions of the brains which help regulate sleep patterns, appetite, and sex drive.

Viral and autoimmune causative factors have been suggested due to the fact that many KLS patients also suffer flu-like symptoms at the onset of the disease. It has also been suggested that an infection may act as a trigger for people who have a genetic disposition towards Kleine-Levin Syndrome.

Treatment and Management
There is no definitive treatment for Kleine-Levin syndrome, however doctors may prescribe certain medications to alleviate the symptoms. Stimulants such as modafinil and methylphenidate can counter the effects of hypersomnia but they do not alleviate the associated cognitive disturbances. Mood altering drugs like carbamazepine and lithium,commonly used to treat bi-polar disorder have also proved beneficial in some cases of KLS.

The charity KLS Support UK suggests that patients should be cared for at home by family members or caregivers to manage anxieties and other disruptive behavior when awake.

Future Research
Since 2005, the KLS Foundation, together with Stanford University Sleep Centre has been conducting a research programme into the causes of Kleine-Levin Syndrome. Anyone diagnosed with the disorder can participate by answering a questionnaire and providing blood samples.
This growing body of data has already yielded some insights into the condition and it is eventually hoped that medical practitioners, scientists and clinicians will eventually be able to determine the cause and treatment for Kleine-Levin Syndrome.


Kleine-Levin Syndrome Support Groups (Alanna Wong’s website)

Kleine–Levin syndrome: Etiology, diagnosis, and treatment

Stanford University KLS Research Programme

Jeff-Mann-Profile-1About the Author

Jeff Mann is the founder of which features news, tips and sleep advice to make you healthier, happier, smarter and more productive. You’ll find the latest research and news about all topics sleep-related. Whether you want to know about insomnia, sleep apnea, getting your baby to sleep or the latest sleep gadgets you’ll find it at

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