Acanthosis Nigricans: Causes, Symptoms and Treatment

Acanthosis Nigricans or Pigmentosa is a skin disorder characterized by areas of darkened, thick, rough and velvety skin. Normally, it affects the flexible areas and folds of the body, such as the armpits, groins, neck folds, elbows, hands and feet.

Among its most common causes are hyperinsulinism, diabetes or obesity, and although there is no specific treatment for its cure, the underlying disease or condition must be treated and some topical drugs can be applied to improve the appearance of the skin.

In very few occasions, this skin condition is a warning sign of the presence of a cancerous tumor in an internal organ, but in the diagnostic this must be taken into account.

acanthosis nigricans

Acantosis Nigricans: Causes

The Acanthosis Nigricans usually occurs in the body when there are high levels of insulin. This excess of insulin can cause the skin cells to reproduce suddenly and, as a result, the skin becomes thicker, darker, velvety and rough in some areas of the body, with the folds of the neck, the underarms, elbows, groins, knees, hands and feet are the most frequent places of appearance.

However, in addition to hyperinsulinism, other possible causes of acanthosis nigricans may be listed below:

  • Genetic disorders.
  • Diabetes.
  • Hormonal disorders, such as slow thyroid, ovarian cysts, problems with the adrenal glands.
  • Overweight and obesity.
  • Consumption of some medications, such as growth hormone, birth control pills, corticosteroids.
  • Stomach, liver, colon, bladder cancer.
  • Lymphoma in genitourinary and gastrointestinal tracts.
  • It has been pointed out that those people with a lot of body weight and a family history of acanthosis nigricans have a higher risk of developing it.

Acanthosis Nigricans: Symptoms

The symptoms of acanthosis nigricans, usually, are reduced to changes in the skin, that is, it does not usually cause the appearance of other physical signs or symptoms. People suffering from this skin disorder tend to present the following:

  • Darkened skin
  • Velvety skin
  • Thicker skin
  • Dark spots or marks in the folds that usually appear in armpits, neck, groin, hands and feet.
  • In some cases, you may feel a little stinging in the affected area.

It is convenient to point out that all these changes that occur in the skin are appearing in a slow and progressive way.

Diagnosis of Acanthosis Nigricans

Normally, acanthosis nigricans is detected when the medical specialist observes the changes in skin appearance mentioned above. On very few occasions, it is necessary to carry out a biopsy of the skin to analyze it later in the laboratory.

However, if the cause of acanthosis nigricans is not clear, the doctor may request a blood test to check the level of glucose in the blood and if there are high levels of insulin, as such as we have previously mentioned, hyperinsulinism is one of the most frequent causes of this cutaneous condition. In addition to the blood test, other medical tests such as x-rays or endoscopy may be required.

Treatment of Acanthosis Nigricans

The treatment of acanthosis nigricans, in the first place, must be intended to treat the underlying disease or condition that is causing these changes in the skin, as this will cause them to shrink or disappear. Therefore, some possible forms of treatment could be the following:

Losing Weight

Those people who have the changes in the skin that produces this skin disorder due to overweight or obesity, it is very important that they put themselves in the hands of a nutritionist and initiate the proper diet to lose weight in a healthy way. It is recommended, above all, reduce the amount of carbohydrates and sugars and include in the diet those foods that are low in calories.

Diabetic Control

Diabetic patients can see how skin lesions are reduced if they keep their disease controlled at all times.

Suspend treatment with medications

In the event that acanthosis nigricans is a consequence of taking a specific drug or supplement, you should consult with the doctor the possibility of suspending the treatment or replacing it with another.


Surgical intervention may be required in those cases in which there is a cancerous tumor and this is the main cause of skin lesions.

Acanthosis Nigricans: Dermatological Treatment

To treat the skin lesions produced by acanthosis nigricans and reduce the discomfort or inconvenience that these cause the affected person, you can resort to the following dermatological treatments:

  • Use of antibiotic creams
  • Application of moisturizing creams on the affected skin, those that contain hydroquinone or ammonium lactate can help to clear the dermis. All topical drugs must be prescribed by a doctor or dermatologist.
  • Wash affected areas with water and mild antibacterial soaps. The cleaning of the skin should be done with care and softness, since the friction could end up worsening the condition.
  • Laser treatments to reduce the thickness of the skin.

Natural remedies such as aloe vera gel, oatmeal cream or cucumber cream can be good options to naturally reduce the visibility of dark spots caused by acanthosis nigricans and to promote rapid recovery of the skin.

Malignant Acanthosis Nigricans: Symptoms

The so-called malignant acanthosis nigricans is uncommon and is associated with the presence of an internal malignant tumor, especially an abdominal gastric adenocarcinoma.

Skin lesions may precede the diagnosis of cancer, so acanthosis nigricans could be one of the first manifestations of this type of cancer. However, in this case, the symptomatology is somewhat different:

  • Skin lesions appear abruptly, spread rapidly and are more severe.
  • They are symptomatic and mucous membranes are often compromised.
  • They are hyperpigmented, rough and hypertrophic lesions.
  • The lips and corners of these are compromised many cases.
  • Usually, acanthosis nigricans coexists with other conditions, such as the Leser-Trelat sign, hyperkeratosis of the palms and soles and cutaneous papillomatosis.

Normally, with the eradication of this tumor, the lesions on the skin disappear, but it can reappear if the tumor is recurrent or metastasize.

Therefore, we can conclude that, especially in those patients who do not have diseases usually associated with acanthosis nigricans, such as diabetes or obesity, a much more exhaustive clinical study should be done, especially when there are signs or indications of a neoplasia.