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

Acanthosis nigricans

Not a rare disease Not a rare disease
Other Names:
AN
Categories:
Acanthosis nigricans (AN) is a skin disorder in which there is darker, thick, velvety skin in body folds and creases. This condition usually appears slowly and doesn't cause any symptoms other than skin changes. Eventually, dark, velvety skin with very visible markings and creases appears in the armpits, groin and neck folds, and over the joints of the fingers and toes. Less commonly, the lips, palms, soles of the feet, or other areas may be affected. The exact cause of this condition is not well understood; but it can be inherited or related to medical problems such as obesity, diabetes mellitus (insulin- resistance), some prescription drugs, and cancer.[1]
Last updated: 8/18/2014

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.

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Medical Terms Other Names
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HPO ID
Percent of people who have these symptoms is not available through HPO
Acanthosis nigricans
Darkened and thickened skin
0000956
Autosomal dominant inheritance 0000006
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Last updated: 7/1/2020
There is no specific treatment for AN. Treatments are used mostly to improve cosmetic appearance and include topical retinoids,  vitamin D creams (such as calcipotriol), dermabrasion and laser therapy. Oral retinoid pills have also been used to treat AN, but are not used for most patients because of the multiple side effects and development problems associated with the treatment. Treatment may also focus on trying to correct the underlying disease that causes AN to develop. Often correcting the underlying disease improves the skin symptoms. Some steps that can be taken depending on the underlying disease include: correcting hyperinsulinaemia through diet and medication, losing weight with obesity-associated AN, removing or treating a tumor, or stopping medications that cause AN.[2][3]
Last updated: 8/18/2014

If you need medical advice, you can look for doctors or other healthcare professionals who have experience with this disease. You may find these specialists through advocacy organizations, clinical trials, or articles published in medical journals. You may also want to contact a university or tertiary medical center in your area, because these centers tend to see more complex cases and have the latest technology and treatments.

If you can’t find a specialist in your local area, try contacting national or international specialists. They may be able to refer you to someone they know through conferences or research efforts. Some specialists may be willing to consult with you or your local doctors over the phone or by email if you can't travel to them for care.

You can find more tips in our guide, How to Find a Disease Specialist. We also encourage you to explore the rest of this page to find resources that can help you find specialists.

Healthcare Resources

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

  • The Centers for Mendelian Genomics program is working to discover the causes of rare genetic disorders. For more information about applying to the research study, please visit their website.
  • ClinicalTrials.gov lists trials that are related to Acanthosis nigricans. Click on the link to go to ClinicalTrials.gov to read descriptions of these studies.

    Please note: Studies listed on the ClinicalTrials.gov website are listed for informational purposes only; being listed does not reflect an endorsement by GARD or the NIH. We strongly recommend that you talk with a trusted healthcare provider before choosing to participate in any clinical study.

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

  • DermNet NZ is an online resource about skin diseases developed by the New Zealand Dermatological Society Incorporated. DermNet NZ provides information about this condition.
  • MedlinePlus was designed by the National Library of Medicine to help you research your health questions, and it provides more information about this topic.
  • The National Organization for Rare Disorders (NORD) has a report for patients and families about this condition. NORD is a patient advocacy organization for individuals with rare diseases and the organizations that serve them.

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 Acanthosis nigricans. 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.

  1. Acanthosis nigricans. MedlinePlus Health Topics. Bethesda, MD: National Library of Medicine; September, 2010; http://www.nlm.nih.gov/medlineplus/ency/article/000852.htm. Accessed 8/15/2014.
  2. Braunstein I. Acanthosis nigricans. In: Callen J, Ofori AO. UpToDate. Waltham, MA: UpToDate; March, 2014; http://www.uptodate.com/contents/acanthosis-nigricans. Accessed 8/15/2014.
  3. Acanthosis nigricans. DermNet NZ. New Zealand: DermNet New Zealand Trust; December 9, 2009; http://www.dermnetnz.org/systemic/acanthosis-nigricans.html. Accessed 8/15/2014.