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What is Acanthosis Nigricans?

Acanthosis Nigricans (AN) is a localized thickening of the skin that often presents with dark brown discoloration commonly in skin folds such as the neck or underarms, although other body parts may also be affected. The condition is usually harmless but may sometimes be associated with other conditions.

Acanthosis nigricans is a skin condition that causes dark, velvety areas to develop on the body due to thickening of the skin. The darkening typically happens slowly and is not harmful, but it can be a warning sign of conditions such as:

  • Weight Gain: Weight gain is often the most common association with acanthosis nigricans
  • Pre-diabetes or diabetes: Endocrine disorders such as diabetes have been associated with acanthosis nigricans
  • Medication reaction: Certain medications may cause darkening of skin
  • Hormonal conditions: Thyroid problems, polycystic ovarian syndrome, Addison’s disease, and other hormonal conditions have been linked to acanthosis nigricans
  • Cancer: In rare cases, acanthosis nigricans can be a warning sign for internal cancer

What are the signs & symptoms of Acanthosis Nigricans?

Patches of thickened and darkened skin associated with acanthosis nigricans occur on various areas of the body, including:

  • Neck
  • Armpits
  • Groin
  • Knees
  • Elbows
  • Under the breasts

The affected skin may be thicker and itchy and may even produce a foul odor. Less commonly, acanthosis nigricans can even develop on the palms, soles of the feet, lips, mouth, and eyelids.

Most times, the condition develops over a period of months or years. Sudden symptoms are indicative of a more serious health issue and should be evaluated by your doctor.

What is the management and treatment of Acanthosis Nigricans?

Acanthosis nigricans is a self-limited condition that may improve when the underlying condition is addressed. Oftentimes, weight loss or management of any underlying diabetes may help improve the appearance of AN.

Although topical exfoliating agents may be used to thin down or exfoliate thickened skin, these options may cause inflammation and irritation of the skin if used in body folds.