What Is Acanthosis Nigricans?
Acanthosis nigricans (ah-kan-THO-sis NY-gruh-kans) causes thicker and darker patches
or streaks around joints and body areas with many creases and folds (such as knuckles,
armpits, elbows, knees, and the sides and back of the neck).

Some people see thicker, darker skin on the palms of their hands, inner thighs,
groin, lips, or other areas. The skin usually stays soft, which is why the word "velvety"
is often used to describe the symptoms of acanthosis nigricans.
Many people who have acanthosis nigricans have no other symptoms and are otherwise
healthy. But because acanthosis nigricans can be a sign of other medical conditions,
it's a good idea for it to be checked out by a doctor.
What Causes Acanthosis Nigricans?
People who are overweight
or obese are more likely to develop acanthosis nigricans, which often lessens
or goes away with weight loss. Some people with the condition inherit it. Some medicines
— for example, birth
control pills or hormone treatments — also can cause acanthosis nigricans.
Sometimes, it's seen in people who have type
2 diabetes or who are at greater risk for getting this type of diabetes. In these
cases, acanthosis nigricans itself isn't dangerous. But it can be a sign to doctors
to check someone for diabetes or other health
problems. Sometimes, finding and treating the health problem might make the person's
skin condition improve or clear up.
Almost 75% of kids with type 2 diabetes develop acanthosis nigricans, according
to the American Diabetes Association. For many, getting their diabetes and weight
(if they are overweight) under control goes a long way toward lessening the visibility
of acanthosis nigricans.
What to Do
Acanthosis nigricans itself isn't harmful or contagious. But you should see a doctor
to make sure it's not caused by something that does need attention. In some cases,
acanthosis nigricans can be a signal that you're at risk for diabetes. Whenever you
notice a change in the color, thickness, or texture of your skin, it's wise to see
a health professional.
What to Expect
If you're diagnosed with acanthosis nigricans, your doctor might want you to have
a blood test or other tests to try to find what's causing it or to look for other
conditions (like type 2 diabetes) that happen more often in people with acanthosis
nigricans.
Treatment for Acanthosis Nigricans
If your doctor finds that your acanthosis nigricans isn't connected to a more serious
medical condition, you don't need to treat it. But you might want to if your doctor
thinks there's a way to help improve the appearance of your skin. Sometimes, acanthosis
nigricans fades on its own.
Your doctor may prescribe lotions or creams. Ask as many questions as you
need to in order to understand when and how to follow the treatment plan.
It's easy to fall into believing the hype about bleaches, skin scrubs, and over-the-counter
exfoliating treatments. But these aren't likely to work and can irritate your skin,
not to mention waste money!
Maintaining a healthy weight by staying physically active and eating well can help
prevent or treat acanthosis nigricans in some cases.
You also should make plans to take care of yourself in other ways. Because this
condition is visible, some people with acanthosis nigricans feel self-conscious or
embarrassed about the way their skin looks. It can help to talk to a counselor, doctor,
friend, or even peer support group to help you feel more confident. Your doctor or
nurse probably can help you find local or online support groups. And don't be afraid
to talk to your friends. Good friends are the best support!
Date reviewed: October 2016