What are warts?
Warts are non-cancerous skin grows that is caused by a viral infection in the top layer of the skin. Viruses that cause warts are called human papilloma virus (HPV). Warts are usually skin colored and feel rough to the touch, but they can be dark, flat, and smooth. The appearance of a wart depends on where it is growing.

How many kinds of warts are there?
There are several different kinds of warts including: Common warts, which are seen on the hands. Plantar warts, which are seen on the bottom of the feet. Flat warts may be seen on the face, arms and legs.

Common warts – Usually grow on the fingers, around the nails, and on the backs of the hands. They are more common where skin has been broken, for example where fingernails are bitten or hangnails picked. These are often called “seed” warts because the blood vessels to the wart produce black dots that look like seeds.

Foot warts – Usually on the soles (plantar area) of the feet and are called plantar warts. When plantar warts grow in clusters, they are known as mosaic warts. Most plantar warts do not stick up above the surface like common warts because the pressure of walking flattens them and pushes them back into the skin. Like common warts, these warts may have black dots. Plantar warts have a bad reputation because they can be painful, feeling like a stone in the shoe. Foot warts are difficult to treat because the bulk of the wart lies below the skin surface. Treatments include the use of salicylic acid plasters, applying other chemicals to the wart, or one of the surgical treatments including laser surgery, electrosurgery, or cutting. The dermatologist may recommend a change in footwear to reduce pressure on the wart and ways to keep the foot dry since moisture tends to allow warts to spread.

Flat warts – These are often too numerous to treat with the standard methods mentioned below. As a result, “peeling” methods using daily applications of salicylic acid, tretinoin, glycolic acid, or other surface peeling preparations are often recommended. For some adults, periodic office visits for surgical treatments are sometimes necessary.

Do warts need to be treated?
In children, warts can disappear without treatment over a period of several months to years. However, warts that are bothersome, painful, or rapidly multiplying should be treated. Warts in adults often do not disappear as easily or as quickly as they do in children.

How do dermatologists treat warts?
Dermatologists are trained to use a variety of treatments. The treatment choice depends on several factors. The age of the patient, the type of warts, the location, and previous therapies will be considered in determining the type of treatment.

Salicylic acid gel – Common warts in young children can be treated at home by their parents on a daily basis by applying salicylic acid gel, solution, or plaster. There is usually little discomfort, but it can take many weeks of treatment to obtain favorable results. Treatment should be stopped at least temporarily if the wart becomes sore.

Cantharidin – Warts may also be treated by “painting” with cantharidin in the dermatologist’s office. Cantharidin causes a blister to form under the wart. The dermatologist can then clip away the dead part of the wart on the blister roof in a week or so.

Cryotherapy – For adults and older children cryotherapy (freezing) is generally preferred. This treatment is not too painful and rarely results in scarring. However, repeat treatments at one to three week intervals are often necessary.

Electrosurgery – This technique uses electrical current (burning) resulting in physical destruction of the skin containing the virus.

Laser – This treatment is considered for warts that have not responded to other therapies. Lasers use heat generated form light to cause physical destruction. There are several different lasers used for the treatment of warts. Lasers are more expensive and require the injection of a local anesthesia to numb the area treated.

Bleomycin – This agent is injected into each wart. It is an anti-cancer drug. The injections may be painful and can have other side effects.

Immunotherapy – This therapy attempts to use the body’s own rejection system to eliminate the virus. Several methods of immunotherapy are being used. With one method, the patient is made allergic to a certain chemical, which is then painted on the wart. A mild allergic reaction occurs around the treated warts, and may result in the disappearance of the warts.

Can I treat my own warts without seeing a doctor?
There are some wart remedies available without a prescription. However, you might mistake another kind of skin growth for a wart, and end up treating something more serious as though it were a wart. If you have any questions about either the diagnosis or the best way to treat a wart, you should seek your dermatologist’s advice.

What about the use of “folk” remedies?
Many people, patients, and doctors alike, believe folk remedies and hypnosis are effective. Since warts, especially in children, may disappear without treatment, it is hard to know whether it was a folk remedy or just the passage of time that led to the cure. Since warts are generally harmless, there may be times when these treatments are appropriate. Medical treatments can always be used if necessary.

What about the problem of recurrent warts?
Sometimes it seems as if new warts appear as fast as old ones go away. This may happen because the old warts have shed virus into the surrounding skin before they were treated. In reality, new “baby” warts are growing up around the original “mother” warts. The best way to limit this is to treat new warts as quickly as they develop so they have little time to shed virus into nearby skin. A check by your dermatologist can help assure the treated wart has resolved completely.

Is there any research going on about warts?
Research is moving along very rapidly. There is great interest in new treatments, as well as the development of a vaccine against warts. Hopefully there will be a solution to the annoying problem of warts in the not too distant future.