Warts are skin growths that are caused by the human papillomavirus (HPV). There are more than 60 kinds of HPV, some of which tend to cause warts on the skin. HPV stimulates quick growth of cells on the skin's outer layer. In most cases, common warts appear on the fingers, near the fingernails, or on the hands. Certain types of HPV can also cause warts to appear in the genital area.
Types of Warts
- Plantar warts: This type of wart usually appears as flesh-colored or light brown lumps that are flecked with small clotted blood vessels that appear as tiny black dots. Plantar warts appear on the soles of the feet.
- Genital warts: Genital warts can appear in the pubic area, on the genitals, in or around the anus, and/or in the vagina. They look like small flesh-colored, pink, or red growths. The warts may look similar to the small parts of a cauliflower or they may be very tiny and difficult to see. They often appear in clusters of three or four, and may grow and spread rapidly. They usually are not painful, although they may cause mild pain, bleeding, and itching. HPV infection is the most common sexually transmitted disease in North America and certain forms of the virus can cause cervical cancer.
- Flat warts: This type of wart is more common in teens and children than in adults. Flat warts are smoother, flatter, and smaller than other warts and they generally occur on the face. Flat warts also can appear on the legs, especially among females.
Warts are caused through direct contact with HPV, which is contagious. HPV may spread by person-to-person contact or through direct contact with an object used by a person with the virus. The virus that causes warts also can spread to other places on the body of the person with warts.
How Are Warts Treated?
In most cases, warts found on the skin are harmless and can disappear without treatment. However, genital warts should be evaluated by a doctor.
Sometimes, warts may recur after treatment and more than one type of treatment may be necessary. Although practitioners attempt to clear warts quickly, most methods require multiple treatments. Treatments may include:
- Freezing: In this treatment, a doctor will use liquid nitrogen to freeze a wart. A blister forms around the wart and the dead tissue falls off within about a week.
- Cantharidin: This substance, an extract of a blister beetle and applied to the skin, forms a blister around the wart. After cantharidin is applied, the area is covered with a bandage. The blister lifts the wart off the skin so the doctor can remove the dead portion of the wart.
- Other medications: These include bleomycin, which is injected into a wart to kill a virus, and Aldara, an immunotherapy drug that comes in the form of a prescription cream. Although Aldara is stated for genital warts, it is modestly effective on other types of warts.
- Minor surgery: When warts cannot be removed by other therapies, surgery may be used to cut away the wart. The base of the wart will be destroyed using an electric needle or by cryosurgery (deep freezing).
- Laser surgery: This procedure utilizes an intense beam of light (laser) to burn and destroy wart tissue.