Warts

Warts are benign growths caused by the human papilloma virus (HPV). Warts are extremely common, especially during childhood. They are generally not harmful, but they can spread and be disfiguring. Picking at warts is discouraged as this may spread them to your fingers or under your nails.

At Dermatology and Laser Institute of Colorado, we specialize in the treatment of warts on all body locations, including fingers, toes, soles, genitals, or body. We see many patients who have been treated elsewhere without success. The following is a list of some of the treatments that we offer. You should keep in mind that no matter what type of treatment you have, multiple treatment sessions will usually be necessary. Sometimes it is necessary to move down the list if one treatment has been tried and has not worked.

• Paring or thinning down your wart at home every few days with a clean blade, pocket knife, pumice stone, or nail file can be helpful. This works best after showering or bathing when the skin is soft. Paring enhances the ability of any treatment to penetrate to the base of the wart. You should try to only remove the dead outer layer of the wart, which should not be very painful.
• Over-the-counter medications generally contain salicylic acid. They are somewhat effective if used on a daily basis for an extended time. It is important to pare the wart as much as possible so that the salicylic acid penetrates.
• Duct tape. You can try wearing duct tape over the wart. Some doctors recommend wearing duct tape on a wart for 6 1/2 days per week, taking a break for 12 hours and then reapplying the duct tape.
• Liquid nitrogen (LN2) is the most common treatment in the office. Freezing with LN2 (-196°C) is safe and nontoxic but somewhat painful. Young children may not tolerate it. Typically a scab or blister forms after a wart is frozen. Treatment with liquid nitrogen can leave a permanent scar.
• Pulsed dye laser (PDL) is available in our office. Treatment with PDL destroys the blood vessels within the wart. High energies are used and treatment can be painful. We usually numb the skin first with injected anesthetic. The treated area will be sore and scabby for a few days afterwards. Treatment with pulsed dye laser can leave a permanent scar.
• Candida antigen (yeast extract) is not FDA-approved for warts but is often injected into one or more warts to try to stimulate an immune reaction against the warts. The immune response sometimes leads to clearing of even distant warts that have not been injected. The area injected may get red, swollen, and tender after injection.
• Bleomycin is a chemotherapy agent and a powerful inhibitor of DNA synthesis. Resistant warts can be treated by injection of bleomycin into the wart (not an FDA-approved use). Although uncommon, Raynaud’s phenomenon and nail abnormalities have been reported after treatment with bleomycin to the fingers. It is not for use in pregnancy.
• Cantharidin (extract of blister beetle, aka “beetle juice”) is not FDA-approved for warts but has been used safely for decades. It is applied topically and allowed to dry on the skin. It is particularly useful in children since it is not painful to apply, although a painful blister usually results. Cantharidin should be washed off after 4-6 hour and any residual blister can be popped with a sterile needle.
• Imiquimod cream is FDA-approved only for the treatment of genital warts in patients age 12 and older, but it is sometimes used for other warts such as flat warts. It works by stimulating your body to locally produce interferon, which has antiviral activity.
• 5-Fluorouracil is a topical chemotherapy drug that inhibits DNA synthesis and is used off-label for warts. It can be applied to the wart twice a day and covered with a bandage or duct tape. It has been reported to rarely cause abnormal nail growth. 5-Fluorouracil can cause significant irritation and is not for use in pregnancy. We often prescribe a compounded product called Wartpeel which contains a proprietary formulation of 5-fluorouracil and salicylic acid in a sustained release vehicle. Wartpeel may not be covered by insurance.
• Cidofovir is a potent antiviral drug which is used to treat various viral infections. It can be compounded into topical form and used off-label to treat resistant warts. Topical cidofovir sometimes works when all other treatments have failed. Topical cidofovir is expensive and may not be covered by insurance.
• Cimetidine is an over-the-counter oral medication that can be used off-label for the treatment of stubborn warts. There is some evidence that it can stimulate the immune system to fight the wart virus, particularly in children. It is generally safe, but some possible side effects include headache and diarrhea and it can interact with other medicines.