Acanthosis Nigricans Is A “Leathery” Skin Condition That’s A Warning Sign Of Diabetes

Acanthosis nigricans… how do you say that now? Try the Mayo Clinic’s pronunciation: ak-an-THOE-sis NIE-grih-kuns.

But pronounce it however you’d like—the real challenge comes in knowing what acanthosis nigricans is and how it relates to diabetes. The condition often occurs with or before type 2 diabetes and may tip off a doctor that someone has type 2. It’s often an indicator of prediabetes or that a person has a high risk of type 2. Less often it’s a sign of cancer.

What is acanthosis nigricans?

Acanthosis nigricans is a skin condition that causes tan or brown raised bumps to appear on your skin near areas with skin folds: usually on the neck, groin, hands, elbows, and knees. The brown patches are usually described as “leathery” or “velvety” and they may cause itching or odor. By itself the condition is annoying, but not dangerous. But the underlying causes can be serious and should be treated.

Photo: flickr/shabash23
Photo: flickr/shabash23

What causes acanthosis nigricans?

The condition may be caused by hormonal disorders, underactive thyroid, certain drugs and supplements (especially hormone-related supplements, corticosteroids, or oral contraceptives), or a cancerous tumor growing in an internal organ.

It’s most often caused by insulin resistance, which is what also can eventually cause type 2 diabetes. When the body’s cells are resistant to insulin, too much insulin remains in the blood. The insulin causes skin cells to reproduce more quickly than usual, and the new skin cells contain more melanin, which means that the new skin will be darker than the skin around it.

Photo: flickr/ana abashidze
Photo: flickr/ana abashidze

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Who’s at risk?

Acanthosis nigricans mostly effects people who are overweight and is more common in those with a family history of the condition. It also more frequently affects those of Native American, African, Caribbean, or Hispanic descent.


Treating the underlying cause of acanthosis nigricans will usually help the skin to clear. If a drug is causing the condition, then discontinuing the drug will usually clear things up. It’s important that a dermatologist or doctor examine you if you’re experiencing symptoms, because the underlying cause could be much more serious than the skin condition itself. If your doctor finds that you have diabetes or prediabetes, treating the underlying condition will improve your overall health and your skin.

Once you know the cause, you can treat that and the skin condition at once. Losing weight will help reduce skin folds and decrease insulin resistance.

Photo: AdobeStock/Alexander Raths
Photo: AdobeStock/Alexander Raths

Treatments specifically for the skin (but not the underlying causes) include:

  • Prescription creams to soften and lighten affected areas
  • Topical antibiotic
  • Acne medications
  • Laser therapy (to reduce thickness)

Acanthosis nigricans is hard to pronounce and frustrating to deal with. But if you’ve been experiencing with the condition without understanding it, you can now take the next steps to start treatment.

Stay healthy, friends!

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