What to Do if Freezing a Wart Doesn T Work
Ugly and annoying, warts never seem to go away fast enough. Treating them may help speed their departure.
Warts are generally harmless and often disappear on their own over time, but they're unsightly, and some, like those found on the soles of the feet, can make walking and exercise painful. Wart removal can be a challenge, but fortunately, the most effective treatments are the least invasive.
Wart anatomy
Warts grow only in the epidermis, the upper skin layer. A typical wart has a raised, rough surface. (Some, like those on the face, may be smooth and flat.) The center of a wart may be flecked with dark dots; these are capillaries that supply it with blood.
What are warts anyway?
Warts occur when skin cells grow faster than normal because they are infected with the human papillomavirus (HPV). Among the 150 strains of HPV, about 10 cause cutaneous (skin) warts, including common, plantar, and flat warts (see "Common types of skin warts," below). Certain other strains cause anal warts and genital warts. Some sexually transmitted types of HPV are implicated in cervical and other genital cancers, but the strains that cause skin warts have rarely been linked to cancer.
All of us come into contact with HPV repeatedly — when we shake hands or touch a doorknob, for example — but only some of us develop warts, and that's hard to explain. Children and people with immune system abnormalities are particularly vulnerable. For reasons that aren't entirely clear, so are people in certain occupations, such as meat, fish, and poultry handlers. But the most likely explanation is that some people are simply more prone to warts than others.
Skin warts aren't highly contagious. They can spread from person to person by direct contact, mainly through breaks in the skin. Theoretically, you can also pick up warts from surfaces such as locker room floors or showers, but there's no way to know how often this occurs. Warts on one part of the body can be spread to other areas, so it's important to wash your hands and anything that touches your warts, such as nail files or pumice stones.
A wart virus infection is different from a bacterial infection such as strep throat, which can be caught, treated, and eradicated because it progresses in a distinct, reliable pattern. The ways of warts are much less predictable. According to dermatologist Dr. Suzanne Olbricht, "The wart virus resides in the upper layer of the skin, and who knows where or when you picked it up? The virus could have been there for years. Then it makes a wart for reasons we don't understand. And when the wart goes away, you can still find the virus in the epidermis."
| Common types of skin warts | ||
| Type | Appearance | Characteristics |
| Common | Raised, rough surface, sometimes with dark specks; light-colored to gray-brown. | Found mostly on the hands, but may appear anywhere. Those under or around the fingernails and toenails can be hard to treat. |
| Plantar | Rough, spongy surface kept flat by walking; gray or brown with dark specks. | Found only on the soles of the feet. Clustered plantar warts are called mosaic warts. |
| Flat | Flat or slightly raised; smooth and pink. Smaller than other warts. | Found mostly on the face, hands, and shins. They're less common than other warts, but when they do appear, it's often in large numbers. |
Treating warts
Studies indicate that about half of warts go away on their own within a year, and two-thirds within two years, so "watchful waiting" is definitely an option for new warts. But some experts recommend immediate treatment to reduce the amount of virus shed into nearby tissue and possibly lower the risk of recurrence. If you prefer not to wait it out, you have several treatment options:
- Salicylic acid. This is the main ingredient in aspirin, and it should usually be your first choice. According to one study, salicylic acid is the only topical treatment (treatment applied directly to the skin) that clearly outperforms a placebo. (The study, in the August 2011 issue of theBritish Journal of Dermatology, combined and reanalyzed data from a number of previous studies.) Salicylic acid costs little, has minimal side effects, and comes in various over-the-counter preparations, including liquids, gels, and patches. Concentrations range from 17% to 40% (stronger concentrations should be used only for warts on thicker skin). To treat a wart, soak it for 10 to 15 minutes (you can do this in the shower or bath), file away the dead warty skin with an emery board or pumice stone, and apply the salicylic acid. Do this once or twice a day for 12 weeks. Warts in thick skin, like the bottom of the foot, may respond best to a patch that stays in place for several days. Continuing treatment for a week or two after the wart goes away may help prevent recurrence.
- Freezing. In this treatment, also called cryotherapy, a clinician swabs or sprays liquid nitrogen onto the wart and a small surrounding area. The extreme cold (which may be as low as –321 F) burns the skin, causing pain, redness, and usually a blister. Getting rid of the wart this way usually takes three or four treatments, one every two to three weeks; any more than that probably won't help. After the skin has healed, apply salicylic acid to encourage more skin to peel off. Some individual trials have found salicylic acid and cryotherapy to be equally effective, with cure rates of 50% to 70%, but there is some evidence that cryotherapy is particularly effective for hand warts.
- Duct tape. Although findings have been mixed, anecdotal evidence suggests that this low-risk, low-tech approach may be worth a try. In one study comparing duct tape with cryotherapy, subjects wore duct tape patches over their warts for six days. Then they removed the patches, soaked and filed the warts, left them uncovered overnight, and reapplied the tape in the morning, leaving them in place for another six days. They followed this regimen for two months or until the wart disappeared. In this study, duct tape was about 45% more effective than cryotherapy. Two other studies found no benefit, but those studies used clear duct tape rather than the standard silver type, which is stickier and has a different kind of adhesive. Given this limited evidence, if you plan to try duct tape, it makes sense to use the silver kind. Why duct tape works isn't clear — it may deprive the wart of oxygen, or perhaps dead skin and viral particles are removed along with the tape. Some people apply salicylic acid before covering the wart with duct tape.
- Other agents. Warts that don't respond to standard therapies may be treated with prescription drugs. The topical immunotherapy drug imiquimod (Aldara), a standard therapy for genital warts, can also be used to treat skin warts. Imiquimod is thought to work by causing an allergic response and irritation at the site of the wart. In an approach called intralesional immunotherapy, the wart is injected with a skin-test antigen (such as for mumps or Candida) in people who have demonstrated an immune response to the antigen. Other agents that may be used to treat recalcitrant warts are the chemotherapy drugs fluorouracil (5-FU), applied as a cream, and bleomycin, which is injected into the wart. All these treatments have side effects, and the evidence for their effectiveness is limited.
- Zapping and cutting. The technical name for this treatment is electrodesiccation (or cautery) and curettage. Using local anesthesia, the clinician dries the wart with an electric needle and scrapes it away with a scoop-like instrument called a curette. This usually causes scarring (so does removing the wart with a scalpel, another option). It's usually reserved for warts that don't respond to other treatments and should generally be avoided on the soles of the feet.
When to see your clinician
Some skin cancers resemble warts at first. If you have a wart that doesn't change much in size, color, or shape, you probably don't need to see a clinician. But if you're in your 50s and develop new warts, consult a dermatologist. Be suspicious of any wart that bleeds or grows quickly.
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What to Do if Freezing a Wart Doesn T Work
Source: https://www.health.harvard.edu/diseases-and-conditions/how-to-get-rid-of-warts