top of page

Acanthosis Nigricans: Causes, Symptoms, Treatment, Prognosis

Updated: Sep 21, 2023

Acanthosis Nigricans St. Louis
Acanthosis Nigricans St. Louis

Ever wondered why some people have dark, velvety patches on their skin? It is a skin condition called acanthosis nigricans. Acanthosis nigricans is characterized by thickened patches that appear in areas with folds or creases like the neck, armpits, and groin. These patches could be a sign of an underlying condition or genetic predisposition. For instance, acanthosis nigricans is more prevalent in individuals with obesity or insulin resistance.

At Mid-County Dermatology in St. Louis, Missouri we diagnose this condition often. It is usually diagnosed visually and rarely requires a skin biopsy. So if you notice these velvety skin folds around your neck or knuckles, or perhaps under your arms (known as axilla), don't ignore them - schedule an appointment with your local dermatologist. Let’s learn more about acanthosis nigricans.

Symptoms of Acanthosis Nigricans

Acanthosis nigricans is a skin condition characterized by the presence of dark, velvety patches of skin that may feel rough or thicker than the surrounding areas. These patches typically appear in body folds such as the neck, armpits, groin, and under the breasts. In some cases, these patches can also become raised and form skin tags.

It is worth noting that individuals with darker skin tones may find that their skin discoloration is more noticeable compared to those with lighter skin tones. The contrast between the dark patches and surrounding skin can be more prominent.

In some instances, acanthosis nigricans can be associated with an underlying medical condition known as malignant acanthosis nigricans. This rare form of acanthosis nigricans is often accompanied by rapid weight loss and other systemic symptoms. If you experience sudden and unexplained weight loss along with changes in your skin, it is essential to seek medical attention promptly.

To summarize:

  • Acanthosis nigricans manifests as dark patches on the skin.

  • These patches are typically found in body folds.

  • Itching or irritation may occur in affected areas.

  • Skin discoloration is more noticeable in individuals with darker skin tones.

  • Malignant acanthosis nigricans, a rare form of the condition, may be accompanied by weight loss.

Causes of Acanthosis Nigricans

Insulin resistance and high levels of insulin are often connected to acanthosis nigricans. When the body becomes resistant to insulin, it compensates by making more insulin. This extra insulin can make skin cells grow, leading to the development of acanthosis nigricans. People with diabetes or pre-diabetes often experience insulin resistance, which makes them more likely to get this condition.

Being very overweight is a big risk factor for getting acanthosis nigricans. Carrying extra weight puts more strain on the body's processes, including how it regulates insulin. Fat cells release hormones that can mess up how insulin works, causing insulin resistance and higher insulin levels. That's why obese people are more prone to getting acanthosis nigricans because of these changes in their metabolism.

Certain medications, hormonal disorders, and genes can also contribute to getting acanthosis nigricans. Some medicines like birth control pills or corticosteroids can cause this skin condition as a side effect. Hormone imbalances linked to conditions such as polycystic ovary syndrome (PCOS) or thyroid disorders can also raise the risk of getting acanthosis nigricans. Genes also play a part in determining how likely someone is to get this condition.

Acanthosis nigricans can also be tied to certain types of cancer or other medical problems. In rare cases, this skin condition can be an early warning sign of an underlying cancer like stomach or liver cancer. If you suddenly develop severe cases of acanthosis nigricans without any clear cause, it's important to see a healthcare professional for further evaluation.

Diagnosis and Differential Diagnosis of Acanthosis Nigricans

To diagnose acanthosis nigricans, a healthcare professional primarily examines the affected areas visually. This condition is characterized by darkened and thickened patches of skin that often appear in skin folds, such as the armpits, neck, and groin. The unique appearance of these patches helps with the diagnosis. However, additional tests may be conducted to confirm the diagnosis and screen for related conditions.

In some cases, blood tests may be recommended to assess insulin levels and detect any underlying hormonal issues. Acanthosis nigricans is commonly associated with insulin resistance or high insulin levels, which can indicate prediabetes or type 2 diabetes. Blood tests can help identify these conditions and guide appropriate treatment.

Differential diagnosis is an important part of diagnosing acanthosis nigricans as it involves ruling out other conditions that cause similar skin changes. There are several syndromes and diseases that exhibit similar symptoms, including:

  • Obesity-related acanthosis nigricans: This form of the condition often occurs in individuals who are overweight or obese due to increased friction and irritation in skin folds.

  • Syndromes associated with acanthosis nigricans: Certain syndromes like polycystic ovary syndrome (PCOS) or Cushing's syndrome can present with acanthosis nigricans as one of their features.

  • Medication-induced acanthosis nigricans: Some medications such as oral contraceptives or high-dose niacin can lead to the development of acanthosis nigricans.

In rare cases where there are concerns about an underlying cancer, a biopsy may be performed. This involves taking a small sample of the affected skin tissue for laboratory analysis. It helps rule out any potential cancerous growths or other serious conditions that may be causing skin changes.

It's important to note that acanthosis nigricans itself is not a disease but rather a symptom of an underlying condition. Therefore, accurate diagnosis and identification of the underlying cause are crucial for proper management and treatment.

Treatment Options for Acanthosis Nigricans

Treating the underlying medical conditions that contribute to acanthosis nigricans is important. This condition is often linked to insulin resistance and obesity, so addressing these factors can greatly improve symptoms. Lifestyle changes play a crucial role in managing acanthosis nigricans.

One of the main treatment approaches is focusing on weight loss and exercise. Losing extra weight can reduce insulin resistance and improve overall health. Regular physical activity not only helps with weight loss but also increases insulin sensitivity, which can lessen the severity of acanthosis nigricans.

Alongside lifestyle changes, there are various creams available that can lighten the affected areas. Dermatologists may prescribe creams containing retinoids (Vitamin A) or keratolytic creams (like Amlactin or urea or salicylic acid or glycolic acid) to be applied directly to the skin. These medications work by promoting cell turnover and reducing darkening, gradually improving the appearance of acanthosis nigricans.

If creams don't give satisfactory results, other options like laser therapy or chemical peels may be recommended. Laser therapy targets the pigmented areas, breaking down excess pigmentation and stimulating collagen production for a more even skin tone. Chemical peels involve applying a chemical solution that removes the top layer of skin, revealing healthier skin underneath.

It's important to know that while these treatments can help manage acanthosis nigricans symptoms, they don't address the root cause. Therefore, treating the underlying medical conditions remains crucial for long-term improvement.

In severe or treatment-resistant cases, additional interventions may be considered:

  • Oral retinoids: These medications, derived from vitamin A, can be prescribed for more widespread or stubborn cases of acanthosis nigricans.

  • Surgical options: In rare instances, surgical procedures like dermabrasion or cryosurgery may be used to remove the affected skin.

Prognosis of Acanthosis Nigricans

Acanthosis nigricans is a skin condition that can have different outcomes depending on what caused it. Although it can be worrying, it's important to know that taking care of any related medical problems can help improve or even get rid of the symptoms.

Doctors who specialize in the skin (dermatologists), hormone-related issues (endocrinologists), and other healthcare professionals all work together to give the best care to people with acanthosis nigricans. This team approach makes sure that all parts of the condition are addressed, including how it affects overall health.

Finding and treating acanthosis nigricans early is really important. If doctors identify it early, they can act quickly and use the right methods to manage it. This not only helps with the symptoms but also lowers the chances of complications.

Understanding what caused acanthosis nigricans is really important too. Sometimes it's related to problems with insulin or being overweight. By making changes in lifestyle and sometimes using medicine, like weight loss programs or medications, people can see their symptoms get better over time.

In some cases, acanthosis nigricans is linked to other medical conditions like polycystic ovary syndrome (PCOS) or hormone imbalances. This is when it's especially important for dermatologists and endocrinologists to work together. They create customized plans to treat both the skin problems and the underlying hormonal issues causing acanthosis nigricans.

Having a primary care doctor (like a general practitioner or GP) on the healthcare team is really important too. They help keep an eye on any other health issues related to acanthosis nigricans and make sure people get regular check-ups.

Conclusion: Understanding Acanthosis Nigricans

It's important to understand acanthosis nigricans so we can identify and manage this skin condition effectively. If someone notices darkened and thickened skin in certain areas, they should seek medical attention promptly. Acanthosis nigricans can be caused by different factors like being overweight, hormone imbalances, or certain medications. It's crucial to see a healthcare professional for an accurate diagnosis and to rule out any other underlying conditions.

The main goal of treating acanthosis nigricans is to address the underlying cause. Making lifestyle changes such as maintaining a healthy weight, exercising regularly, and eating a balanced diet can significantly improve the condition. A healthcare provider may also prescribe creams or ointments to help reduce the appearance of dark patches on the skin.

Although acanthosis nigricans itself is not harmful, it might indicate a higher risk of developing health issues like diabetes or polycystic ovary syndrome (PCOS). Regular monitoring of blood sugar and hormone levels is important to manage these potential risks.

To get the best results when dealing with acanthosis nigricans, it's recommended to work with a healthcare team that includes dermatologists, endocrinologists, nutritionists, and other specialists. They can create personalized care plans based on individual needs.

Taking action against acanthosis nigricans involves not only treating the visible symptoms but also addressing any underlying health concerns that might contribute to its development. By making positive lifestyle changes and following medical advice, individuals can improve their overall well-being and possibly prevent further complications associated with this condition.


Q: Can acanthosis nigricans be cured completely?

A: While there is no definitive cure for acanthosis nigricans at present, it can be managed effectively through lifestyle modifications and targeted treatments.

Q: Is acanthosis nigricans a sign of diabetes?

A: Acanthosis nigricans can be associated with insulin resistance, which is commonly seen in individuals with type 2 diabetes. However, not all cases of acanthosis nigricans are indicative of diabetes.

Q: Can weight loss help improve acanthosis nigricans?

A: Yes, losing weight through healthy lifestyle changes such as regular exercise and a balanced diet can often lead to an improvement in the appearance of acanthosis nigricans.

Q: Are there any medications that can worsen acanthosis nigricans?

A: Certain medications, such as oral contraceptives and high-dose niacin, have been linked to the development or exacerbation of acanthosis nigricans in some individuals.

Q: Can children develop acanthosis nigricans?

A: Yes, children can develop acanthosis nigricans. It is important to consult a healthcare professional for proper evaluation and management if this condition is observed in children.

Please note that these FAQs are provided for informational purposes only and should not replace professional medical advice. It is always recommended to consult with a healthcare provider for personalized guidance regarding your specific situation.

If you feel that you may have acanthosis nigricans, call us at 314-994-0200 or schedule online with one of our St. Louis dermatologists to confirm.

142 views0 comments


bottom of page