Acanthosis nigricans is a condition that causes the skin to thicken and darken typically in an area where there are skin folds such as the armpits, groin and the back of the neck. The skin takes on a velvety texture and skin tags may also develop in the affected area. The color of acanthosis nigricans can range from brown to black and sometimes stretch marks appear on the surrounding skin.
The most common cause of acanthosis nigricans is related to conditions that raise the level of insulin in the blood. People with type 2 diabetes and those who are overweight have extra demand on their body requiring higher levels of insulin be produced. The higher levels of insulin are thought to make the cells more sensitive and susceptible to these skin changes.
Other causes of acanthosis nigricans may be due to medications such as birth control pills. Hormones problems from endocrine disorders may also contribute and it is possible for acanthosis nigricans to be inherited. Acanthosis nigraicans is also more common in those with darker skin.
Treatment is aimed at the underlying condition that has caused acanthosis nigricans. A routine physical will help determine if the person is having insulin balance problems or another medical/endocrine diseases. Lab work will be drawn to investigate if there are imbalances in hormone levels such as with thyroid disease or Addison’s disease.
If obesity is found to be the main cause then a diet to lose weight would be suggested as well as a change in diet to reduce sugar and starch intake.
Other direct skin treatments include:
• Retin A type creams may lighten and increase healing of the skin and alpha-hydroxy acid lotion acts to help the skin hold in moisture.
• Fish oil supplements are thought to improve the quality of the skin and also increase moisture.
• Accutane or similar type of oral medication helps shed the layers of thickened skin and prevents or treats other acne eruptions.
• Dermabrasion or laser treatments help remove thickened skin and lighten it.
• Antibacterial soap controls bacterial growth on thickened skin to prevent infections.