A wart is typically a small, rough, non-cancerous tumor that grows on the top layer of skin. Warts often resemble a solid blister or a cauliflower, and can seem either very light or very dark compared to the normal skin surrounding it. Warts are usually painless, but can cause itching and burning if they are in high-friction areas.

Warts are caused by a viral infection called the human papillomavirus virus (HPV). The HPV is contagious and can be passed from person to person by either direct or indirect contact. The virus can also spread from one body location to another on the same person. The virus enters the body through an area of skin that is cracked, peeling, or moist. The amount of virus present, the location of contact, and the state of a person's immune system are all factors that determine if an HPV infection will cause a wart to form.

There are many different kinds of warts, including common warts, flat warts, plantar warts, and genital warts. The common wart is generally raised and dome-shaped with a rough, grayish-brown surface. These warts usually grow on the fingers or the backs of the hands and are sometimes called "seed warts” because they contain little blood vessels that look like black seeds.

A flat wart is a small, slightly elevated, smooth wart which is usually pink, light brown, or flesh colored. These warts are most commonly seen on the face and forehead of an infected person. They can occur in large numbers, with as many as 100 flat warts clustered together. They are more common in children than in adults and are also called “juvenile warts.”

Plantar warts grow on the pressure points on the bottom of the feet, and large numbers of these warts may cause difficulty with walking, running, jumping, and even standing. Several plantar warts can cluster together in one area and are called “mosaic warts.” Plantar warts usually resemble a thick callous, so it is a good idea to have a physician diagnose that the growth really is a wart before treating it.

Genital or venereal warts grow on the genitals, in the pubic area, between the thighs, and inside the vagina and anal canal. Transmitted through sexual activity, genital warts can vary in size from small, shiny papules to large cauliflower-like lesions. Genital warts are likely to reoccur because there is no cure for the virus that causes them and because warts thrive in moist environments. Because chemicals can really harm the genital area, these warts should only be treated by qualified medical personnel.

Most warts will eventually disappear on their own, expelled by the body's immune system. However, warts can also last for years or repeatedly reoccur. Although warts are not life-threatening, many people think they are disfiguring and wish to have them removed.

There are several ways a physician can remove a wart. The most common method is cryosurgery, which involves freezing the wart with a special chemical, usually liquid nitrogen, after which the deadened wart will soon falls off. This treatment is not too painful and rarely results in scarring.

Electrosurgery, which entails burning the wart off, is another good alternative treatment. Some physicians use laser treatments to remove warts, but this procedure tends to be more expensive. Physicians can also treat warts with keratolysis, which uses salicylic acid to remove the dead surface skin cells.

There are several over-the-counter options for wart removal available at supermarkets and drugstores. The most popular treatments involve salicylic acid or silver nitrate. These procedures will require several treatments to remove a wart. Over-the-counter cryosurgery kits are also available, but they cost much more than the other treatments.

It is important to realize that these over-the-counter treatments can kill healthy skin as well as warts, so people must be extremely careful when applying them. It is always a good idea to seek a physician’s advice before treating any type of questionable skin growth.