Acanthosis nigricans is a disease that causes dark, thick areas on the skin. The areas affected are spread out, and the skin is velvety. It is most common in the armpits and other body folds.
There are four types of acanthosis nigricans.
There are many causes of acanthosis nigricans, including the following:
Acanthosis nigricans causes skin lesions that are darker than the skin around them. The lesions have a velvety feel. The lesions often form in the folds along the neck, armpits, groin, knuckles, between the legs, at the elbow, under the breasts, and around the belly button.
A doctor can diagnose acanthosis nigricans by doing a medical history and physical exam.
When acanthosis nigricans is caused by obesity, weight management is key. When it is caused by cancer, there may be little that can be done to prevent it until the cancer is successfully treated. Acanthosis nigricans caused by medicine may go away once the medicine is stopped.
A person with acanthosis nigricans may have chafing of the skin. These areas do not become cancerous. The appearance of these chafed spots bothers some people.
Acanthosis nigricans is not catching and poses no risk to others.
Treatments of acanthosis nigricans include the following:
Side effects of steroid creams and ointments include stretch marks and thinning of the skin. Retinoids can cause birth defects if taken by a pregnant woman.
The doctor may recommend treatment for an underlying condition or disease. For example, obese people may be advised to lose weight to lower their insulin resistance. A person who has diabetes will need to keep blood glucose levels under good control.
The disease or condition that is causing acanthosis nigricans will need to be monitored. Any new or worsening symptoms should be reported to the doctor.
Author:James Broomfield, MD
Date Written:
Editor:Crist, Gayle P., MS, BA
Edit Date:08/17/02
Reviewer:Eileen McLaughlin, RN, BSN
Date Reviewed:08/20/01