Warts
What is it?
Warts are common, benign skin growths caused by a viral infection. Usually appearing on the hands, elbows, face, and soles of the feet, warts may also be located on the genitals (see Genital Warts for more information). Nongenital warts are harmless and only mildly contagious. There are a number of different types of warts, named for their location on the body and their appearance: common warts (verrucae vulgaris) are most often seen on the hands and fingers; plantar warts are located on the soles of the feet (see Plantar Warts); periungual warts are located around the nails of fingers and toes; digitate warts are small fingerlike projections that appear on the scalp or face; filiform warts are thin, threadlike projections commonly found around the face and neck; flat warts may occasionally occur in groups of up to several hundred at a time.Many warts disappear spontaneously within one or two years, or removal may be attempted with a variety of treatments. Because the virus may be present in neighboring tissues, recurrence is common. As people grow older, however, most develop an immunity to warts.
What Causes It?
- Warts are caused by the human papillomavirus (HPV), of which there are more than 60 types. The virus enters the skin through tiny breaks and can be transmitted by direct physical contact with another person. For the most part, warts are only mildly contagious (with the exception of genital warts).
- People with weakened immune systems—such as those infected with HIV or undergoing treatment with immunosuppressant medications—have a higher risk for developing widespread, persistent warts.
- Contrary to popular belief, you cannot get warts from handling frogs or toads.
Prevention
- You can use an electric razor or depilatory in lieu of a conventional razor to prevent nicks that may promote the spread of warts on the face or legs.
- Do not scratch existing warts.
Diagnosis
- Diagnosis can be made by observation of the characteristic appearance and does not usually require a doctor.
How to Treat It
- In healthy people most warts (including genital warts) will heal without treatment in six months to three years, when the body develops an immune response.
- Wart removal preparations containing salicylic or lactic acid are available over the counter. Do not use these wart removal preparations to remove facial or genital warts; such preparations are too harsh for sensitive facial and genital skin.
- Warts may be removed by freezing them off (cryosurgery), by laser surgery, or by electrocautery (burning warts off with an electric current). These treatments can be painful, may leave scars, and are not first-line therapies for young children.
- Topical tretinoin (Retin-A), a vitamin A derivative, may be prescribed to treat flat warts.
- Your doctor may apply caustic chemical solutions such as cantharidin or trichloroacetic acid to destroy the warts.
When to Call a Doctor
- Make an appointment with a doctor or dermatologist if you want warts removed; anticipate more than one visit as warts are often resistant to treatment.
- See a doctor if you are over age 45 and develop warts or are unsure of the diagnosis of warts.
- New or unusual skin growths should be evaluated to rule out skin cancer.
- See a doctor if you or your sexual partner develops genital warts.
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Copyright © 2008 Medletter Associates, LLC
Content excerpted from Johns Hopkins Symptoms and Remedies: The Complete Home Medical Reference.