There are actually several different types of warts that affect the skin, and include the following:
* Common wart (Verruca vulgaris): raised wart with roughened surface, most common on hands and knees
* Flat wart (Verruca plana): small, smooth flattened wart, tan or flesh coloured, most common on the face, neck, hands, wrists and knees and in large numbers
* Filiform or Digitate wart: a thread- or finger-shaped wart, most commonly appearing on the face, especially near the eyelids and lips
* Plantar wart (verruca, Verruca pedis): a hard lump which often has multiple black specks in the center; generally found on pressure points on the soles of the feet.
* Mosaic wart: a group of tightly clustered plantar-type warts, commonly on the hands or soles of the feet
There are several direct methods doctors use to treat warts. The most common include:
* Keratolysis, which is removal of dead surface skin cells. This is usually done by applying salicylic acid, blistering agents, or formaldehyde.
* Cryosurgery, which involves freezing the wart with liquid nitrogen
* Surgical curettage (scraping) of the wart.
* Laser treatment.
* Application of Cantharidin, which is a chemical derived from the green blister beetle. The cantharidin causes the skin under the wart to blister, lifting the wart off the skin.
There are also several over-the-counter options available, including:
* Salicylic acid, which comes in the form of adhesive pads treated with salicylic acid or in a solution form. To treat warts using salicylic acid, the affected area must first be cleaned throughly before applying the acid. The resulting dead skin must be cleared away with a pumice stone or emery board, and the process repeated until the wart is removed. It can take several weeks of treatment to remove the wart.
* Silver nitrate which is available as a caustic pencil. This method generally takes three to six daily treatments to be effective.