Rare Pediatrics News

Disease Profile

Kleine Levin syndrome

Prevalence estimates on Rare Medical Network websites are calculated based on data available from numerous sources, including US and European government statistics, the NIH, Orphanet, and published epidemiologic studies. Rare disease population data is recognized to be highly variable, and based on a wide variety of source data and methodologies, so the prevalence data on this site should be assumed to be estimated and cannot be considered to be absolutely correct.

1-9 / 1 000 000

US Estimated

Europe Estimated

Age of onset





Autosomal dominant A pathogenic variant in only one gene copy in each cell is sufficient to cause an autosomal dominant disease.


Autosomal recessive Pathogenic variants in both copies of each gene of the chromosome are needed to cause an autosomal recessive disease and observe the mutant phenotype.


dominant X-linked dominant inheritance, sometimes referred to as X-linked dominance, is a mode of genetic inheritance by which a dominant gene is carried on the X chromosome.


recessive Pathogenic variants in both copies of a gene on the X chromosome cause an X-linked recessive disorder.


Mitochondrial or multigenic Mitochondrial genetic disorders can be caused by changes (mutations) in either the mitochondrial DNA or nuclear DNA that lead to dysfunction of the mitochondria and inadequate production of energy.


Multigenic or multifactor Inheritance involving many factors, of which at least one is genetic but none is of overwhelming importance, as in the causation of a disease by multiple genetic and environmental factors.


Not applicable


Other names (AKA)

Kleine-Levin hibernation syndrome; Familial Kleine-Levin syndrome; Familial hibernation syndrome


Congenital and Genetic Diseases; Nervous System Diseases


Kleine Levin syndrome is a rare disorder characterized by recurrent episodes of excessive sleep (hypersomnia) along with cognitive and behavioral changes. Affected individuals may sleep for up to 20 hours per day during an episode. These episodes usually last for a few days to a few weeks. An episode may start abruptly and is sometimes preceded by an upper-respiratory-type infection. During an episode, people with Kleine Levin syndrome can also display abnormal behavior, such as excessive food intake (hyperphagia), irritability, childishness, disorientation, hallucinations, and an abnormally uninhibited sex drive. Affected individuals are symptom-free between episodes. The time between episodes varies. Kleine Levin syndrome primarily affects adolescent males, but it also affects females and individuals of other ages. The underlying cause of this condition is unknown. Episodes tend to decrease with advancing age. There are no consistently effective therapies, although stimulants (modafinil, methylphenidate, amphetamine) and mood stabilizers (lithium) may be prescribed with varying results.[1][2][3][4]


This table lists symptoms that people with this disease may have. For most diseases, symptoms will vary from person to person. People with the same disease may not have all the symptoms listed. This information comes from a database called the Human Phenotype Ontology (HPO) . The HPO collects information on symptoms that have been described in medical resources. The HPO is updated regularly. Use the HPO ID to access more in-depth information about a symptom.

Medical Terms Other Names
Learn More:
Percent of people who have these symptoms is not available through HPO
Autosomal dominant inheritance
Easily confused
Mental disorientation

[ more ]

Episodic hypersomnia
Voracious appetite
Vivid hallucinations


Support and advocacy groups can help you connect with other patients and families, and they can provide valuable services. Many develop patient-centered information and are the driving force behind research for better treatments and possible cures. They can direct you to research, resources, and services. Many organizations also have experts who serve as medical advisors or provide lists of doctors/clinics. Visit the group’s website or contact them to learn about the services they offer. Inclusion on this list is not an endorsement by GARD.

Organizations Supporting this Disease

    Learn more

    These resources provide more information about this condition or associated symptoms. The in-depth resources contain medical and scientific language that may be hard to understand. You may want to review these resources with a medical professional.

    Where to Start

      In-Depth Information

      • Medscape Reference provides information on this topic. You may need to register to view the medical textbook, but registration is free.
      • The Monarch Initiative brings together data about this condition from humans and other species to help physicians and biomedical researchers. Monarch’s tools are designed to make it easier to compare the signs and symptoms (phenotypes) of different diseases and discover common features. This initiative is a collaboration between several academic institutions across the world and is funded by the National Institutes of Health. Visit the website to explore the biology of this condition.
      • Online Mendelian Inheritance in Man (OMIM) is a catalog of human genes and genetic disorders. Each entry has a summary of related medical articles. It is meant for health care professionals and researchers. OMIM is maintained by Johns Hopkins University School of Medicine. 
      • Orphanet is a European reference portal for information on rare diseases and orphan drugs. Access to this database is free of charge.
      • PubMed is a searchable database of medical literature and lists journal articles that discuss Kleine Levin syndrome. Click on the link to view a sample search on this topic.


        1. NINDS Kleine-Levin Syndrome Information Page. National Institute of Neurological Disorders and Stroke. https://www.ninds.nih.gov/Disorders/All-Disorders/Kleine-Levin-Syndrome-Information-Page. Accessed 6/5/2017.
        2. Arnulf I. Kleine-Levin Syndrome. Sleep Med Clin. Jun 2015; 10(2):151-61. https://www.ncbi.nlm.nih.gov/pubmed/26055863.
        3. Miglis M, Guilleminault C. Kleine-Levin Syndrome. Curr Neurol Neurosci Rep. Jun 2016; 16(6):60. https://www.ncbi.nlm.nih.gov/pubmed/27137943.
        4. Afolabi-Brown O, Mason TB. Kleine-Levin Syndrome. Paediatr Respir Rev. Dec 23, 2016; https://www.ncbi.nlm.nih.gov/pubmed/28216256.