A small, fleshy bump on the skin or mucous membrane caused by human papillomavirus.

In most cases, your doctor can diagnose a common wart with one or more of these techniques.

• Examining the wart
• Scraping off the top layer of the wart to check for signs of dark, pinpoint dots — clotted blood vessels — which are common with warts
• Removing a small section of the wart (shave biopsy) and sending it to a laboratory for analysis to rule out other types of skin growths

TREATMENT

Most common warts go away without treatment, though it may take a year or two and new ones may develop nearby. Some people choose to have their warts treated by a doctor because home treatment isn't working and the warts are bothersome, spreading or a cosmetic concern.

The goals of treatment are to destroy the wart, stimulate an immune system response to fight the virus, or both. Treatment may take weeks or months. Even with treatment, warts tend to recur or spread. Doctors generally start with the least painful methods, especially when treating young children.