National Center for Advancing and Translational Sciences Genetic and Rare Diseases Information Center, a program of the National Center for Advancing and Translational Sciences

Non 24 hour sleep wake disorder


Other Names:
Circadian rhythm sleep disorder, free-running type; Hypernychthemeral syndrome
Categories:
Non 24 hour sleep wake disorder refers to a steady pattern of one- to two-hour delays in sleep onset and wake times in people with normal living conditions. This occurs because the period of the person's sleep-wake cycle is longer than 24 hours. The condition most commonly affects people who are blind, due to an impaired sense of light-dark cycles.[1][2][3] Non 24 hour sleep wake disorder can also affect sighted people. The cause of the disorder in these cases is incompletely understood, but studies suggest melatonin levels play a role.[3]
Last updated: 6/3/2014

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.

Showing of 6 |
Medical Terms Other Names
Learn More:
HPO ID
30%-79% of people have these symptoms
Abnormal pineal melatonin secretion 0012689
Asthenia 0025406
Blindness 0000618
Depressivity
Depression
0000716
Excessive daytime sleepiness 0002189
Excessive daytime somnolence
More than typical sleepiness during day
0001262
Showing of 6 |
Last updated: 7/1/2020

FDA-Approved Treatments

The medication(s) listed below have been approved by the Food and Drug Administration (FDA) as orphan products for treatment of this condition. Learn more orphan products.

Research helps us better understand diseases and can lead to advances in diagnosis and treatment. This section provides resources to help you learn about medical research and ways to get involved.

Clinical Research Resources

  • Orphanet lists European clinical trials, research studies, and patient registries enrolling people with this condition. 

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

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.

In-Depth Information

  • 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.
  • 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 Non 24 hour sleep wake disorder. Click on the link to view a sample search on this topic.

Questions sent to GARD may be posted here if the information could be helpful to others. We remove all identifying information when posting a question to protect your privacy. If you do not want your question posted, please let us know. Submit a new question

  • Is non 24 circadian disorder genetic in sighted people? See answer


  1. Judd BG, Sateia MJ. Classification of sleep disorders. In: Basow M. UpToDate. Waltham, MA: UpToDate; 2014; Accessed 6/2/2014.
  2. Hayakawa T, Uchiyama M, Kamei Y, Shibui K, Tagaya H, Asada T, Okawa M, Urata J, Takahashi K. Clinical analyses of sighted patients with non-24-hour sleep-wake syndrome: a study of 57 consecutively diagnosed cases. Sleep. August 1, 2005; 28(8):945-52. http://www.ncbi.nlm.nih.gov/pubmed/16218077. Accessed 6/2/2014.
  3. Uchiyama M et al. Larger phase angle between sleep propensity and melatonin rhythms in sighted humans with non-24-hour sleep-wake syndrome. Sleep. 2002 Feb 1; 25(1):83-8. http://www.ncbi.nlm.nih.gov/pubmed/11833864. Accessed 6/3/2014.