Seborrheic Keratosis

Seborrheic keratosis is a common, noncancerous (benign) skin growth that can occur anywhere on the skin. It looks like "stuck-on," waxy, rough, tan, brown, or black spots on the skin. These skin growths can be flat or raised. They are often called "barnacles" because of their pasted-on appearance. Usually, these skin growths appear in adulthood, around age 30, and increase in number as you age. They may also develop during pregnancy or following estrogen therapy. Many people may only have one growth appear in their lifetime, while some people may develop many growths.


It is unknown what causes these skin growths, but they appear to run in families.


Seborrheic keratosis is often located on the face, chest, shoulders, back, or other areas. These growths are:

  • Usually painless, but may become irritated and itchy.

  • Yellow, brown, black, or other colors.

  • Slightly raised or have a flat surface.

  • Sometimes rough or wart-like in texture.

  • Often waxy on the surface.

  • Round or oval-shaped.

  • Sometimes "stuck-on" in appearance.

  • Sometimes single, but there are usually many growths.

Any growth that bleeds, itches on a regular basis, becomes inflamed, or becomes irritated needs to be evaluated by a skin specialist (dermatologist).


Diagnosis is mainly based on the way the growths appear. In some cases, it can be difficult to tell this type of skin growth from skin cancer. A skin growth tissue sample (biopsy)  may be used to confirm the diagnosis.


Most often, treatment is not needed because the skin growths are benign. If the skin growth is irritated easily by clothing or jewelry, causing it to scab or bleed, treatment may be recommended. Patients may also choose to have the growths removed because they do not like their appearance. Most commonly, these growths are treated with cryosurgery.

In cryosurgery, liquid nitrogen is applied to "freeze" the growth. The growth usually falls off within a matter of days. A blister may form and dry into a scab that will also fall off. After the growth or scab falls off, it may leave a dark or light spot on the skin. This color may fade over time, or it may remain permanent on the skin.


If the skin growths are treated with cryosurgery, the treated area needs to be kept clean with water and soap.


  • You have questions about these growths or other skin problems.

  • You develop new symptoms, including:

  • A change in the appearance of the skin growth.

  • New growths.

  • Any bleeding, itching, or pain in the growths.

  • A skin growth that looks similar to seborrheic keratosis.