What is Kleine-Levin (sleeping beauty syndrome)?

Sleeping Beauty Syndrome (Kleine-Levin syndrome) is a severe sleeping disorder that can cause someone to sleep for six months. It will be interesting to explore its symptoms, causes and treatments.

A girl with sleeping beauty syndrome (kleine-levin disorder)

Sleeping beauty is not just a fairytale after all!

From Baby Boomers down to Gen Z, Sleeping Beauty is a popular movie. In the 1959 Walt Disney movie - "Sleeping Beauty", a witch cursed a newborn princess. The curse was that the princess would die on her 16th birthday. However, a fairy alters the curse by making the princess go into a deep sleep that a kiss from a true lover can only break.

Perhaps, Kleine-Levin syndrome got its other name from this Walt Disney movie.

Kleine-Levin syndrome (KLS) is colloquially known as sleeping beauty syndrome. Sleeping beauty syndrome is a rare sleep disorder characterised by recurring periods of excessive sleepiness accompanied by hypersexuality, altered perception, cognitive dysfunction and polyphagia.

People with sleeping beauty syndrome can sleep for up to 20 hours in a day. KLS sleep disorder can affect anyone; however, teenage boys and males are mostly affected.

Sleeping beauty syndrome episodes reoccur over an extended period. Sometimes, the episode disappears for as long as ten years. When a person is experiencing an episode, it affects the person's normal life. School, work and other daily life activities can be affected.

BBC News told the story of Beth Goodier, a young girl with sleeping beauty syndrome. Goodier sleeps for 22 hours a day during her KLS episodes. The article described KLS as a "very devastating condition" which makes a victim exhibit "child-like behaviour".

More than 500 cases of Kleine-Levin syndrome have been reported in medical literature, although there are high chances that some cases go underdiagnosed.

From scientists' estimation, sleeping beauty syndrome affects 1 to 5 people out of every one million people. Its prevalence is also higher among Ashkenazi Jews.

Symptoms of sleeping beauty syndrome

The New York Post reported the case of a 17-year old Columbian girl with sleeping beauty syndrome who slept for 70 consecutive days. The girl, Sharik Tovar, suffers from Kleine-Levin syndrome. The condition affected her memory, causing her to forget her mother's face temporarily.

According to the National Organization for Rare Diseases, people with sleeping beauty syndrome may wake up occasionally or be woken up at intervals to eat or use the bathroom.

People with Kleine-Levin syndrome may exhibit 2 to 12 episodes in a year. They may also go for months or years without experiencing any episode. Episodes of the syndrome become less frequent with age and may disappear eventually.

Because Kleine-Levin (KLS) symptoms are cyclical, affected individuals may be unable to carry out some tasks or take care of themselves for the period when the syndrome symptoms are present.

Symptoms of sleeping beauty syndrome include:

  • Excessive sleeping (hypersomnolence)
  • Irritability, lethargy or apathy when woken up
  • Excessive eating (compulsive hyperphagia)
  • Weight gain
  • Depression
  • Anxiety
  • Aggression
  • Hallucinations
  • Disorientation
  • Fatigue
  • Abnormal sexual drive
  • Absentmindedness and difficulty with concentration
  • Memory problems
  • Childish behaviour
  • Other behavioural abnormalities

Causes of sleeping beauty syndrome

Photo source: Shutterstock

The cause of sleeping beauty syndrome is still unknown. However, scientists believe that its symptoms may be a result of dysfunction of the hypothalamus. The hypothalamus is the part of the brain that regulates body functions, including sleep and appetite.

An injury to the hypothalamus, e.g., falling and hitting the head, could cause sleeping beauty syndrome.

There are also cases of people developing Kleine-Levin syndrome after an infection such as the flu. This made researchers speculate that a dangerous pathogen harming the hypothalamus may cause the syndrome.

Another speculated cause of sleeping beauty syndrome is autoimmunity. This means the body's immune system may mistake its own hypothalamic brain tissue for a foreign invader and attack, causing damage to the hypothalamus.

There are also few cases where sleeping beauty syndrome appears multiple times in one family, suggesting that genetics may be one of the causes of sleeping beauty syndrome.

Researchers have hypothesized that causes of sleeping beauty syndrome include:

  • Physical trauma
  • Infection
  • Toxins
  • Psychological problems
  • Autoimmunity

Is there a cure for sleeping beauty syndrome?

There is no conclusive cure for sleeping beauty syndrome. According to the National Institute of Neurological Disorders and Stroke (NINDS), there is no definitive treatment for sleeping beauty syndrome.

One of the ways to help a person suffering from Kleine-Levin syndrome is by watching and waiting over them, ensuring they wake up at intervals to eat, use the restroom, etc.

A doctor might also prescribe for the patient stimulant pills such as modafinil and amphetamines to treat sleepiness.

How to know if you have a sleeping beauty syndrome

The only way to find out if you have sleeping beauty syndrome is through diagnosis. If you notice you experience excessive sleeping episodes that occur periodically, you should talk to your doctor or visit a healthcare facility for proper diagnosis.

To be diagnosed with sleeping beauty syndrome, an individual must first show signs of recurrent hypersomnia. According to the Sleep Foundation, the signs of recurrent hypersomnia include:

  • Episodes of excessive sleep that lasts between 2 to 5 days
  • Excessive sleep episodes that occur at least once every 18 months or more frequently
  • Normal cognition and behaviour between episodes

Typically, doctors first rule out the possibility of the patient suffering from other conditions with similar symptoms as Kleine-Levin syndrome.

The level of brain activity slows down by as much as 70% during sleep in people with Kleine-Levin syndrome. This is also helpful for diagnosing if a person has sleeping beauty syndrome or not. Sleep tests can be used to measure electrical activity in the brain.

Sleeping beauty syndrome treatment

Photo source: Shutterstock

Treatment for sleeping beauty syndrome consists of supportive care and medication-assisted therapy (MAT).

Supportive care for Kleine-Levin syndrome patients

Living with Kleine-Levin syndrome can significantly impact a person's life, interfering with daily activities and routines. Patients will need lots of supports from friends and family members.

Caregivers can help people suffering from Kleine-Levin syndrome by:

  • Ensuring the patient is always in a safe and comfortable environment to avoid danger in case of an unanticipated episode
  • Monitoring and supervising the patient
  • Preventing the patient from driving or operating heavy machines
  • Postponing the patient's activities such as school until the KLS episode is over
  • Watching out for psychological symptoms of KLS such as depression, anxiety and suicidal behaviour

Managing sleeping beauty syndrome with medications

There are available medications for managing sleeping beauty syndrome. However, physicians usually prescribe medications only as a secondary treatment. Medicines may help prevent future episodes, reduce symptoms and the duration of an episode.

Medications typically prescribed include stimulants like modafinil, amphetamine and methylphenidate. These drugs promote wakefulness; however, they can cause irritability.

Mood disorder medications such as carbamazepine and lithium might also help relieve some symptoms of Kleine-Levin syndrome.


Kleine-Levin syndrome, also known as sleeping beauty syndrome, is not a life-threatening condition. However, it can interfere with a person's regular life routine. Reaching out to healthcare professions for treatment helps manage the disease.

Feel free to talk to your doctor regarding how you feel and about your symptoms. Since an episode can hit you at any point, it will help to learn how to identify an upcoming episode.

Sleepiness and tiredness due to the sleeping beauty syndrome can occur suddenly, e.g., when you are driving. Identifying an impending episode will enable you to stay away from a potentially dangerous situation before it hits you.


  1. Aran, A, Mignot, E. and Arnulf, I. (2020). Kleine-Levin syndrome (recurrent hypersomnia).
  2. Frishberg, H. (2019). Girl with 'sleeping beauty' disorder sleeps for weeks.
  3. Krychman, M. and Zwerling, B. (2020). 003 Sleeping beauty syndrome: A rare sleep sexuality disorder.
  4. Lanese, N. (2020). Girl with rare sleeping beauty syndrome' dozes for months.
  5. Millichap, J. G. (2005). Kleine-Levin Syndrome.
  6. National Institution of Neurological Disorders and Stroke (NINDS). (2019). Kleine-Levin Syndrome Information Page.
  7. National Organization for Rare Disorders (NORD). Kleine-Levin Syndrome.
  8. Shoen, S. (2021). Kleine-Levin Syndrome.