Share this page

Health Library

Acanthosis Nigricans

Pronounced: AAY-can-THO-sis NIG-ruh-cans

Definition

Acanthosis nigricans is a skin condition in which brown or black velvet-like markings appear under the arms, in the groin, or on the back of the neck. Any skin fold can be affected, including the lower lip and chin.

Causes

Causes of acanthosis nigricans may include:

  • High insulin levels in people who are obese
  • A family history of acanthosis nigricans
  • Rarely, a cancerous tumor
Risk Factors

Acanthosis nigricans is more common in people of African-American decent. Other factors that increase your chances of getting acanthosis nigricans include:

Symptoms

Symptoms include velvety-looking, dark areas anywhere on the skin.

Diagnosis

Your doctor will ask about your symptoms and medical history. A physical exam will be done. Tests may include the following:

  • Skin biopsy
  • Blood tests
  • X-rays
  • Endoscopy

Endoscopy

Endoscope in stomach

Copyright © Nucleus Medical Media, Inc.

Treatment

Treatment often involves treating the underlying cause. For example, if acanthosis nigricans is due to obesity, weight loss can improve the skin condition.

Topical and oral retinoids and other medicines have been reported to improve appearance in some cases. They help remove excess layers of skin.

Prevention

To reduce your chances of getting acanthosis nigricans, take these steps:

  • Maintain a healthy weight
  • Eat a balanced diet
  • Get regular exercise most days of the week
  • Talk to your doctor about your blood sugar levels

RESOURCES

National Organization for Rare Diseases
http://www.rarediseases.org

American Academy of Dermatology
http://www.aad.org

CANADIAN RESOURCES

Dermatologists.ca
http://www.dermatologists.ca

Health Canada
http://www.hc-sc.gc.ca

References

Acanthosis nigricans. EBSCO DynaMed website. Available at: https://dynamed.ebscohost.com/about/about-us. Updated December 10, 2010. Accessed June 3, 2013.

Clark N, Stulberg DL, et al. Common hyperpigmentation disorders in adults: part II. Melanoma, seborrheic keratoses, acanthosis nigricans, melasma, diabetic dermopathy, tinea versicolor, and postinflammatory hyperpigmentation. Am Fam Physician. 2003;68(10).

Katz AS, Goff DC, et al. Acanthosis nigricans in obese patients: presentations and implications for prevention of atherosclerotis vascular disease. Dermatol Online J. 2000;6(1):1.

10/15/2010 DynaMed's Systematic Literature Surveillance https://dynamed.ebscohost.com/about/about-us : Kong AS, Williams RL, et al. Acanthosis nigricans and diabetes risk factors: prevalence in young persons seen in southwestern US primary care practices. Ann Fam Med. 2007;5(3):202-208.
Kong AS, Williams RL, et al. Acanthosis Nigricans: high prevalence and association with diabetes in a practice-based research network consortium—a PRImary care Multi-Ethnic network (PRIME Net) study. J Am Board Fam Med. 2010;23(4):476-485.



Last reviewed June 2013 by Brian Randall, MD

Please be aware that this information is provided to supplement the care provided by your physician. It is neither intended nor implied to be a substitute for professional medical advice. CALL YOUR HEALTHCARE PROVIDER IMMEDIATELY IF YOU THINK YOU MAY HAVE A MEDICAL EMERGENCY. Always seek the advice of your physician or other qualified health provider prior to starting any new treatment or with any questions you may have regarding a medical condition.

Baptist Flame

Baptist Health Systems

Find A Doctor

Services

Locations

Baptist Medical Clinic

Patients & Visitors

Learn

Contact Us

Physician Tools

Careers at Baptist

Employee Links

Online Services

At Baptist Health Systems

At Baptist Medical Center

close ×