Randy Jacobs, M.D. Patient Education

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Warts are common growths on the skin caused by a virus. Warts may grow on any part of the skin. For example, warts on the feet are called plantar warts. It takes one to six months to develop warts after exposure to the wart virus. Like the common cold virus, the wart virus is contagious and is spread by direct person-to-person contact. Once a person has warts, he may spread warts to other parts of his own body. When considering treatment, about 65% of warts disappear within two years without any treatment at all. The problem is contagion. If warts are untreated, they will certainly spread to others. Warts are due to a slow growing virus and may take many weeks to months to grow. Despite what you have heard, frogs do not cause warts.

What Causes Warts?

Warts occur as a result of infection with the human papillomavirus. We have identified over 41 HPV subtypes. Unique HPV subtypes cause warts on specific body areas.


Are there different kinds of warts?

Yes. Common warts are thick and rounded with a rough, grayish surface. They are usually found on the fingers, hands, elbows, chest, back, and knees. Plantar warts appear on the soles of the feet and, unlike other warts, grow inward. Flat warts are thin and smooth and are seen most often on the back of the hands and on the face. Genital warts affect the genitalia and rectal area of both men and women.


Are warts contagious? Can their spread be prevented?

Warts are contagious and are usually spread by skin-to-skin contact. Condoms may provide protection against the transmission of genital warts. Children acquire warts by touching other people with warts, usually a playmate. Plantar warts are usually contacted at the gym or from a contaminated shoe, shower, or bathroom floor.


Should warts be treated?

Most warts require treatment. Common and flat warts should be removed to prevent multiplication or spread to other areas. Plantar warts can cause pain and discomfort as they grow and may make walking difficult. Warts can destroy fingernails and can spread.


How are warts removed?

There are a number of different therapies. Certain therapies may not be FDA recognized. The wart may be coated with a topical agent, such as salicylic acid, 5-fluorouracil cream, Verrusol, or Cantharone “blister beetle juice.” Laser surgery and electrical destruction are becoming widely used, especially for genital warts. Warts can also be frozen with liquid nitrogen, surgically scraped, burned, or cauterized. Aldara is a new wart medicine FDA approved for genital warts. Aldara is not FDA approved for common warts, but many dermatologists prescribe Aldara for their wart patients, especially for difficult warts of the fingers and face. Please understand that most wart removal methods cause irritation, pain, blisters, and wounds.


Is it possible for warts to return?

Recurrence rates may be as high as 30%-45%. Treatments destroy visible warts, but may not eradicate the virus, which can persist in a latent state. At some point the virus may begin replicating, causing warts to recur. Until there is a drug to kill HPV or a vaccine to give immunity, all we can do is treat visible warts and depend on the body's immune system to keep the HPV virus in check.

Do warts ever go away without treatment?

After several months or years, a wart may disappear spontaneously in response to the body's immune system. The body slowly builds up its defense against the wart, and a triggering event makes it suddenly launch an attack. People with suppressed immune systems, such as patients who have undergone transplantation or chemotherapy, may be unable to rid themselves of warts, no matter what treatment is used.


Can the wart virus cause cancer?

Certain HPV types have been linked with a variety of premalignant and malignant conditions. Genital warts are the greatest cause for concern. Women who have had genital warts or sexual contact with someone with genital warts have a significant risk of developing cervical neoplasia (cancer). For this reason, among others, it is critical that genital warts be treated.



Ask your pharmacist for “40% Mediplast,” or “40% Wart Stick,” or an equivalent over the counter Salicylic Acid wart medicine and a Pumice Stone.


Here are the steps:

1. At bedtime, put the wart-destroying medicine on the warts.


2. After applying the medicine, cover your warts with adhesive tape. Use the old-fashioned fabric type of adhesive tape. The tape keeps your skin moist. The moisture softens the surface of the warts so the wart medicine can penetrate and go to work.


3. After a few days the outside of the warts will start to turn gray. This means the chemical has begun to destroy them. Scrape this gray wart tissue off with a pumice stone every second or third day. Do the scraping after your bath or shower has softened the wart's surface.


4. Be sure to remove every bit of dead wart tissue. Sometimes small curved scissors can help in trimming the dead wart tissue. Whatever you use for scraping your warts should not be used for anything else, because warts are contagious. Do not let anyone else use your pumice stone. Clean your pumice stone by dipping in alcohol.


5. If the warts become too sore, stop the wart treatments for a few days.


6. If your plantar warts hurt when you stand or walk, wear a pad cut out of Dr. Scholl's Adhesive Foam (available without prescription). Cut a hole (or holes) corresponding to where the warts are. This pad will take pressure off and can relieve your pain.



7. Continue the treatment until you believe the warts are gone. If you can see the lines of your skin crossing the treated area, the warts are probably gone. If it turns out that after you stop treatment you see that the warts are still there, start treating them again until you feel more certain that the warts have gone away.


8. If necessary, continue the treatment for two to four months. If the warts haven't been significantly destroyed after four months of treatment, return to the derm clinic.


9. If your warts become excessively painful or infected, return at once to the clinic.