Acanthosis Nigricans

Acanthosis Nigricans

What is acanthosis nigricans?

Acanthosis nigricans is a skin disorder characterized by itchy thick dark patches that can give off offensive smells. These patches can be found where there are folds on the skin, on the knuckles, on the feet, on the elbows, on the palms, knees, lips, armpits, neck, groin, and on the sole of the feet.
When you find this patch in any of those places on your body, there is something wrong somewhere in your body. In fact, it might be a sign of diabetes. If you report to a doctor immediately, they will properly diagnose and treat whatever the problem is and once that has been done, off, the patches will go.

Who is at risk for acanthosis nigricans?

If you are a man, you are at a risk. If you are a woman, you are at risk, too. If you have too much bad fat in your body, that is, overweight, you are already implicated. If your skin is very dark, you are at risk. If you have a history of diabetes in your family, you are susceptible. Even kids can be affected. As a matter of fact, any child who develops acanthosis nigricans will likely develop type 2 diabetes much later in life.
And according to the American Academy of Dermatology, if you are Hispanic, Caribbean, or African, then you may be at risk of this condition. It was even said that your risk is very high. Other ethnic groups are not excluded. They will be at an equal risk if there body mass index is above normal.
Body mass index measures the weight of your body with respect to your height. It is one of the yardsticks for classifying people into different weights – underweight, normal, overweight, obesity.
Acanthosis nigricans

Photo Credit: NHS

Causes of acanthosis nigricans


The skin patches associated with acanthosis nigricans is caused by abnormal rapid reproduction of skin cells called the epidermal cells. Epidermal cells are found in the epidermis of the skin. The epidermis is the surface of the skin, the one you can see, feel, touch, and hold.
The hormone responsible for the rapid growth of the epidermal cells is called insulin. It is produced in the pancreas. It is the number one cause of it. Just as the popular saying that too much of everything is bad, too much of insulin in the blood is bad. It is the cause of the patches.
Well, too much insulin is not the only cause of rapid epidermal cell reproduction. Cancerous conditions, medications, and pretty other factors can be responsible for it. But these are always in rare cases.
Whenever you eat rice, bread, yam, and those other types of energy-giving you love eating, glucose is produced in your body. Glucose is one of the molecules that give the energy necessary for all the activities in your body to take place and keep you alive. While some of this molecule will be utilized, others will be stored in the cells of the body (i.e. in the liver, brain, etc.) for use. Insulin makes this storage to be possible. It allows these cells to be sensitive to glucose.

Being overweight

Why an overweight person might be at a higher risk of developing acanthosis nigricans is because their pancreatic cells are not sensitive to insulin. Hence, glucose will not be able to enter the cells. A large concentration of it and insulin will then pile up in the blood.
Increased blood insulin will definitely induce the rapid production of epidermal cells. This will mean more melanin production if the person is already dark-skinned. It is this increase in melanin that now produces the dark skin patch that is darker than its surrounding skin environment


Women who take contraceptive pills may be at risk of acanthosis nigricans.
Chemotherapy medications, growth hormones, thyroid regimen, and certain supplements used in building the body can be responsible for this skin anomaly. Discontinuing of any of these medications put an end to the abnormal reproduction of epidermal cells.
Other possible causes exist. They are

  1. Cancer of the stomach: Gastric adenocarcinoma is a very good example.
  2. Disorders of the adrenal gland: an example is Addison’s disease.
  3. Abnormal conditions of the pituitary gland.
  4. Low blood concentration of thyroid hormones
  5. High dosage of niacin.

Diagnosis of acanthosis nigricans

By mere examining your skin, it can be diagnosed.  Your doctor will ask you a few questions about your current medications. Make sure you open up to him all the medications you are on. You will thus be evaluated. But in order to be sure it is the one, a confirmatory test will be carried out on you. The common test that will be done is a blood glucose test. A fasting insulin test can also be conducted.
On rare occasions, your doctor could insist on performing a small skin biopsy test on that place where the patch is so as to zero out other likely causes.

How is acanthosis nigricans treated?

Since acanthosis nigricans is not a disease but a symptom of an underlying disease, it is the disease that is crucial and should be treated. The disease must be diagnosed to find its cause. Only then can it be treated.
If it is because of excess body fat, you should already know that you will be asked to begin a weight loss therapy. But while you are yet to start this, medications will be given to you to put your blood insulin level under control.
And if it is because of the medications and supplements you have been taking, you will be advised to stop them. If the medications are vital to your health, an alternative will be prescribed for you.

Cosmetic treatments

Very likely, if the dark patches are located in places that are very sensitive like your lips, neck, etc. you might not be comfortable with it. You will want to get rid of it by all means. You can consider the following treatment options. They are not curative because they will only help in clearing those patches. They do not address the actual cause of the patches.

  1. Retin-A: It is a skin lightener. It is composed of salicylic acid, alpha-hydroxy acids, and about 20% urea.
  2. Antibacterial soaps
  3. Medications for acne of the mouth.
  4. Heat (laser) therapy.

Ongoing care and prevention

Based on the cause of the condition, you will be instructed on what to do. Such instructions will involve checking your weight and if possible, shed some pounds. This will be by a change in your lifestyle, exercising as often as thrice a week, checking what you eat, and indeed whatever medications you are currently on.
Generally, keeping fit can lower your risk of not just acanthosis nigricans but of other diseases.
Learn more >>>>> Skin Care: The Complete Guide to Maintaining a Glowing Skin for Life

Recent posts