Acanthosis nigricans is a skin condition that causes patches of dark, thickened, velvety skin to develop on the neck, underarms, thighs, or groin. It isn’t harmful or contagious, although you may not like its appearance.
Acanthosis nigricans can be a sign of other medical conditions, so it’s important to bring it up with your healthcare provider.
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Acanthosis Nigricans Symptoms
With acanthosis nigricans, dark, thickened, velvety skin slowly develops in areas of the body where there are skin folds, typically the armpits, underarms, groin, and the fold of the neck.
The pigmentation may also appear over the joints in the fingers and toes.The affected skin stays soft and doesn’t toughen.
Some people call the line on the neck the sugar line or sugar necklace (due to its association withdiabetes). Less often, the pigmentation appears on the lips, palms, or soles of the feet, which is associated with cancer.
Causes
Acanthosis nigricans can affect otherwise healthy people, and it is not always related to a medical condition.
However, it is associated with these conditions:
Insulin Resistance and Acanthosis NigricansInsulin resistanceis a condition in which the body is resistant to the effects ofinsulin.Insulin causes glucose to be taken into the body cells to be used for energy. Someone with insulin resistance will require larger amounts of insulin for glucose to be taken into the body tissues.
Insulin Resistance and Acanthosis Nigricans
Insulin resistanceis a condition in which the body is resistant to the effects ofinsulin.Insulin causes glucose to be taken into the body cells to be used for energy. Someone with insulin resistance will require larger amounts of insulin for glucose to be taken into the body tissues.
Insulin resistanceis a condition in which the body is resistant to the effects ofinsulin.
Insulin causes glucose to be taken into the body cells to be used for energy. Someone with insulin resistance will require larger amounts of insulin for glucose to be taken into the body tissues.
Diagnosis
Discuss your skin changes with your healthcare provider, who will examine your skin and can usually diagnose it based on its appearance.
Your practitioner may order blood sugar levels or insulin levels. In some cases, endoscopy or X-rays are needed to check for cancer and other causes.
Treatment
Primary treatment of acanthosis nigricans aims to correct the underlying cause. It is reversible and will disappear as the cause is treated.Weight lossand reversing insulin resistance are the most effective ways to eliminate the skin changes.
Topical retinoids increase the shedding of normal skin cells, which can reduce the appearance of the lesions.
Frequently Asked QuestionsAcanthosis nigricans are dark patches of thickened, velvety skin. It commonly appears on the neck, thighs, or groin and is often confused at first with dirt-crusted skin.Its exact cause is unknown, but it is associated with obesity, polycystic ovary syndrome, type 2 diabetes, genetic disorders, and certain cancers. You can also have acanthosis nigricans without any other medical conditions.Yes, acanthosis nigricans is more common among people with diabetes than in the general population. However, you can have acanthosis nigricans even if you don’t have diabetes.If acanthosis nigricans is due to a medical condition, such as diabetes, treating the underlying disease can help clear up dark patches of skin. Weight loss and exercise to reverse insulin resistance can often fade acanthosis nigricans.Yes, a dermatologist can offer specialized treatments for acanthosis nigricans. Treatments include topical retinoids, dermabrasion, or laser therapy.
Frequently Asked Questions
Acanthosis nigricans are dark patches of thickened, velvety skin. It commonly appears on the neck, thighs, or groin and is often confused at first with dirt-crusted skin.Its exact cause is unknown, but it is associated with obesity, polycystic ovary syndrome, type 2 diabetes, genetic disorders, and certain cancers. You can also have acanthosis nigricans without any other medical conditions.
Acanthosis nigricans are dark patches of thickened, velvety skin. It commonly appears on the neck, thighs, or groin and is often confused at first with dirt-crusted skin.
Its exact cause is unknown, but it is associated with obesity, polycystic ovary syndrome, type 2 diabetes, genetic disorders, and certain cancers. You can also have acanthosis nigricans without any other medical conditions.
Yes, acanthosis nigricans is more common among people with diabetes than in the general population. However, you can have acanthosis nigricans even if you don’t have diabetes.
If acanthosis nigricans is due to a medical condition, such as diabetes, treating the underlying disease can help clear up dark patches of skin. Weight loss and exercise to reverse insulin resistance can often fade acanthosis nigricans.
Yes, a dermatologist can offer specialized treatments for acanthosis nigricans. Treatments include topical retinoids, dermabrasion, or laser therapy.
6 SourcesVerywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read oureditorial processto learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.Kapoor S.Diagnosis and treatment of acanthosis nigricans.Skinmed.2010;8(3):161-4.American Academy of Dermatology.Acanthosis nigricans: Signs and symptoms.Kota SK, Tripathy PR, Kota SK, Jammula S.Type 2 diabetes mellitus: An unusual association with Down’s syndrome.Indian J Hum Genet. 2013;19(3):358-9. doi:10.4103/0971-6866.120818American Academy of Dermatology.Acanthosis nigricans: Who gets and causes.Bahadursingh S, Mungalsingh C, Seemungal T, Teelucksingh S.Acanthosis nigricans in type 2 diabetes: prevalence, correlates and potential as a simple clinical screening tool - a cross-sectional study in the Caribbean.Diabetol Metab Syndr.2014;6:77. doi:10.1186/1758-5996-6-77National Institute of Diabetes and Digestive and Kidney Disease.Insulin resistance and prediabetes.Additional ReadingNg HY.Acanthosis nigricans in obese adolescents: prevalence, impact, and management challenges.Adolesc Health Med Ther. 2017;8:1-10. doi:10.2147/AHMT.S103396
6 Sources
Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read oureditorial processto learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.Kapoor S.Diagnosis and treatment of acanthosis nigricans.Skinmed.2010;8(3):161-4.American Academy of Dermatology.Acanthosis nigricans: Signs and symptoms.Kota SK, Tripathy PR, Kota SK, Jammula S.Type 2 diabetes mellitus: An unusual association with Down’s syndrome.Indian J Hum Genet. 2013;19(3):358-9. doi:10.4103/0971-6866.120818American Academy of Dermatology.Acanthosis nigricans: Who gets and causes.Bahadursingh S, Mungalsingh C, Seemungal T, Teelucksingh S.Acanthosis nigricans in type 2 diabetes: prevalence, correlates and potential as a simple clinical screening tool - a cross-sectional study in the Caribbean.Diabetol Metab Syndr.2014;6:77. doi:10.1186/1758-5996-6-77National Institute of Diabetes and Digestive and Kidney Disease.Insulin resistance and prediabetes.Additional ReadingNg HY.Acanthosis nigricans in obese adolescents: prevalence, impact, and management challenges.Adolesc Health Med Ther. 2017;8:1-10. doi:10.2147/AHMT.S103396
Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read oureditorial processto learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.
Kapoor S.Diagnosis and treatment of acanthosis nigricans.Skinmed.2010;8(3):161-4.American Academy of Dermatology.Acanthosis nigricans: Signs and symptoms.Kota SK, Tripathy PR, Kota SK, Jammula S.Type 2 diabetes mellitus: An unusual association with Down’s syndrome.Indian J Hum Genet. 2013;19(3):358-9. doi:10.4103/0971-6866.120818American Academy of Dermatology.Acanthosis nigricans: Who gets and causes.Bahadursingh S, Mungalsingh C, Seemungal T, Teelucksingh S.Acanthosis nigricans in type 2 diabetes: prevalence, correlates and potential as a simple clinical screening tool - a cross-sectional study in the Caribbean.Diabetol Metab Syndr.2014;6:77. doi:10.1186/1758-5996-6-77National Institute of Diabetes and Digestive and Kidney Disease.Insulin resistance and prediabetes.
Kapoor S.Diagnosis and treatment of acanthosis nigricans.Skinmed.2010;8(3):161-4.
American Academy of Dermatology.Acanthosis nigricans: Signs and symptoms.
Kota SK, Tripathy PR, Kota SK, Jammula S.Type 2 diabetes mellitus: An unusual association with Down’s syndrome.Indian J Hum Genet. 2013;19(3):358-9. doi:10.4103/0971-6866.120818
American Academy of Dermatology.Acanthosis nigricans: Who gets and causes.
Bahadursingh S, Mungalsingh C, Seemungal T, Teelucksingh S.Acanthosis nigricans in type 2 diabetes: prevalence, correlates and potential as a simple clinical screening tool - a cross-sectional study in the Caribbean.Diabetol Metab Syndr.2014;6:77. doi:10.1186/1758-5996-6-77
National Institute of Diabetes and Digestive and Kidney Disease.Insulin resistance and prediabetes.
Ng HY.Acanthosis nigricans in obese adolescents: prevalence, impact, and management challenges.Adolesc Health Med Ther. 2017;8:1-10. doi:10.2147/AHMT.S103396
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