What is Kleine-Levin syndrome (KLS)?

Dr. Mehmet Oz, MD
Cardiology (Cardiovascular Disease)
Kleine-Levin Syndrome (KLS) is a rare neurological disorder that causes episodes of extreme sleepiness and unusual wakeful behaviors. It is sometimes referred to as Sleeping Beauty syndrome because people with KLS can spend more than 12 hours at a time sleeping. Episodes can last from days to weeks, and can last from months to years. It primarily affects teen boys and may be triggered by a bacterial or viral infection, fever, alcohol or marijuana use, trauma or sleep deprivation.  People with KLS can wake up spontaneously to go to the bathroom or eat, but often they need to be aroused to do it. When they are awake or prevented from sleeping they can become irritable, aggressive and confused. Strange eating behaviors and cravings are not unusual. They can have voracious appetites eating considerably more than usual and consume and crave copious amounts of sugar and syrupy foods. During wakefulness, a small minority of sufferers may experience an overwhelming need to masturbate, fondle or expose themselves and to make inappropriate sexual advances or shout obscenities.
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Kleine-Levin syndrome is a rare disorder that primarily affects adolescent males (approximately 70 percent of those suffering from KLS are male). KLS is characterized by recurring, but reversible, periods of excessive sleep (up to 20 hours per day). Symptoms occur as "episodes," typically lasting a few days to a few weeks. Episode onset is often abrupt, and may be associated with flu-like symptoms. Excessive food intake, irritability, childishness, disorientation, hallucinations, and an abnormally uninhibited sex drive may be observed during the episodes. Depression can be a consequence, but not a cause, of the disorder. Affected individuals are completely normal between episodes, however they may not be able to recall everything that happened during the episode. It may be weeks or more before symptoms reappear. Symptoms may be related to malfunction of the hypothalamus and thalamus, parts of the brain that govern appetite and sleep.
This answer is based on source information from the National Institute of Neurological Disorders and Stroke .

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