What are Symptoms of Acanthosis Nigricans?

Signs of this skin condition include:

• Patches of brown or black skin.
• Skin that feels velvety.
• Skin tags.
• Itchiness.
• Foul-smelling skin patches.

Symptoms tend to appear slowly, over months or even years. If these signs appear suddenly, see a dermatologist. It may be a sign of cancer.

Diagnosis and Tests

How is acanthosis nigricans diagnosed?

Your healthcare provider will talk to you about your symptoms and medical history and perform a physical exam. Often, these steps are enough to diagnose AN. Other tests to diagnose AN include:

• Blood work, which can help confirm or rule out underlying conditions such as diabetes.
• Skin biopsy (taking a sample of skin tissue), on rare occasions, if the diagnosis is not straightforward.

Management and Treatment

Will acanthosis nigricans go away on its own?

AN will not go away on its own, but you don’t always need medical treatment. If no underlying condition is causing AN, you can decide if you want to treat the dark patches.

Is acanthosis nigricans reversible?

People typically see good results after treatment. The skin clears, although the dark spots may not go away completely.

What treatments are available for acanthosis nigricans?

Treatment for AN depends on the cause. If AN is due to an underlying condition, such as diabetes or a hormonal condition, treating the condition will treat the skin problems.

Often, weight loss, exercise and a nutritious diet help reduce insulin levels, resulting in improved skin. The patches may even disappear completely.

Other treatments include:

• Prescription creams to lighten the area.
• Laser therapy or dermabrasion to reduce thickness.
• Antibiotics to get rid of odor or discomfort.
• Retinoids to help clear the skin.
• Stopping certain medications that are causing AN.

Do not use skin care products to treat dark spots without consulting with a healthcare provider. These products may not work and may even irritate your skin, worsening the condition.

How can I manage acanthosis nigricans?

If the AN is related to elevated insulin, managing your weight and eating a healthy diet can help prevent or reduce the dark spots.

Prevention

Can acanthosis nigricans be prevented?

If obesity is causing AN, you can help prevent the condition through weight management. A diet that helps you keep your blood sugar (insulin) levels in check can also help prevent AN.

Other preventive steps include:

• Managing medical conditions related to AN, such as thyroid problems and diabetes.
• Avoiding medications, such as birth control pills, that can cause or worsen AN.

Outlook / Prognosis

What is the outlook for people with acanthosis nigricans?

AN isn’t dangerous or harmful. People can live normal, healthy lives with AN.

However, it’s important to manage conditions that may be causing AN, such as diabetes, obesity or hormonal conditions. And if the dark patches appear suddenly, see your healthcare provider immediately. The sudden appearance may be a sign of cancer.

Living With

When should I see a dermatologist about acanthosis nigricans?

Any time you notice changes in your skin, see your healthcare provider or a dermatologist. Small markings or changes may seem insignificant, but they may indicate a problem. Acanthosis nigricans can be a sign of prediabetes or diabetes. Talk to your provider so you can get the proper care.

A note from Cleveland Clinic

Acanthosis nigricans is a treatable skin condition that causes dark patches on your body. It is often (though not always) a sign of prediabetes or diabetes. Talk to your healthcare provider to find out if you have an underlying condition causing AN. A healthcare provider can help you get treatment to reduce the marks and help you feel and look your best.