Seborrheic keratoses are harmless growths of the skin. Also called the barnacles of aging, these spots become more numerous as a person gets older. 
Pregnancy and estrogen therapy may also cause eruptions of these lesions, according to the <a href="[BASEDOMAIN]/healthinfo/bouncelink.aspx?shortcut=aad" target="_blank">American Academy of Dermatology</a>.
What do they look like? 
Seborrheic keratoses may appear individually or in clusters. They range in color from tan to dark bluish-black. 
They are identified by their waxy, stuck-on look. The spots may begin as small bumps on the skin and develop a wartlike crust. 
Treatment 
Though these blemishes are not a health threat, people may decide to have them removed. Treatments for removing seborrheic keratoses include: 
<ul>
 <li>Cryotherapy, when liquid nitrogen is used to freeze the lesions. </li>
 <li>Scraping the lesions from the skin after administering a local anesthetic. </li>
 <li>Electrosurgery, which uses an electric current to burn off the lesion after it is numbed. </li>
</ul>
Always worth a closer look 
Seborrheic keratoses are benign, but it is important to distinguish between these and other blemishes that could be precancerous. Ask your doctor to check any skin growths or lesions. 
Reviewed 9/8/2023

Your skin: What are seborrheic keratoses?

These growths resemble warts and, like warts, can be removed. But they pose no health threat.