What are the signs that wart removal is successful
A secondary infection developing in the site of cryosurgery is uncommon. The symptoms include:
What to know about freezing warts
We include products we think are useful for our readers. If you buy through links on this page, we may earn a small commission Here’s our process.
How we vet brands and products
Medical News Today only shows you brands and products that we stand behind.
- Evaluate ingredients and composition: Do they have the potential to cause harm?
- Fact-check all health claims: Do they align with the current body of scientific evidence?
- Assess the brand: Does it operate with integrity and adhere to industry best practices?
Cryosurgery, or cryotherapy, is a common way to remove warts. It involves freezing off the targeted cells and tissues.
Warts are noncancerous tumors that develop due to human papillomavirus (HPV) infections. There are several different types of wart, and various strains of HPV can cause them. This virus passes on through skin-to-skin contact .
Most warts are painless and harmless, and many go away on their own after a few weeks or months , though they can last years.
Part of the reason for these long wait times and short appointments is due to a nationwide shortage of physicians that is only getting worse. A report by the Association of American Medical Colleges predicts that, due to population growth and specifically growth of the elderly population, the physician shortfall in the U.S. could reach 121,300 by the year 2030.
But depending on the location, size, and type of a wart, a person may wish to have it removed. In this case, cryosurgery is an option. A dermatologist can perform it, or, for a smaller wart, a person might try an over-the-counter freezing kit.
In this article, we explore cryotherapy, including the procedure, the reasons that people have it, and how effective it is.
A dermatologist usually begins by scraping dead skin cells from the wart with a scalpel. This exposes more of the surface skin containing the virus to the freezing agent, which is liquid nitrogen.
In some cases, the doctor may instruct the person to perform this scraping at home the night before the appointment.
They may also recommend applying salicylic acid gels, creams, and bandages beforehand. These products are available to purchase online.
Next, the dermatologist uses a probe, cotton ball, dipstick, or a tool called a cryostat gun to deliver a dose of liquid nitrogen to the wart. Preferences and methods of application vary, but all in all, the liquid nitrogen is typically in contact with the skin for 10–20 seconds.
Within 24 hours of the procedure, a blister forms around the wart. After about 1 week, it may be possible to remove this blister along with the wart.
Current guidelines recommend having two cryosurgery sessions for wart removal, but more may be necessary, depending on the size of the wart.
A 2011 study found that leaving 2, as opposed to 3, weeks between cryotherapy sessions may reduce the risk of the wart regrowing and minimize any adverse effects.
Liquid nitrogen-based removal is safe for most healthy people. A dermatologist may recommend a different approach, however, depending on the person’s age and the overall state of their health.
It is not always necessary to remove warts through cryosurgery. They often resolve without treatment, especially in children.
As people move into adulthood, they may find that warts require medical intervention, especially if they:
- cause discomfort or pain
- cause friction or pressure
- have persisted for more than a few years
- cause or contribute to low self-esteem, anxiety, or depression
- keep a person from walking comfortably or gripping objects, or cause any other impairment
- are plantar warts, which form on the soles
It other cases, health issues make it important to see a professional. The American Academy of Dermatology recommend that people with any of the following see a dermatologist for wart removal:
- diabetes
- a compromised immune system
- multiple warts across the body
- warts that bleed, itch, or hurt
- warts on the face or genitals
Though many doctors remove warts with cryosurgery, there is limited research to support using this procedure rather than concentrated salicylic acid treatment.
However, cryotherapy may be the most effective approach to certain kinds of warts. For example, a 2012 review found that the procedure had a 60–86% success rate as a treatment for common and genital warts.
A retrospective study from 2015 placed the success rate for common wart removal at 75% and found that it took an average of 1.18 sessions to remove warts with cryosurgery.
A 2019 study found a slightly higher success rate for the cryosurgical removal of genital warts: 79–88% . The researchers also found that it was safe during pregnancy.
Plantar warts tend to be both the hardest to treat, as they grow inward due to pressure on the feet. Large warts can also be difficult to manage.
It is important to note that cryosurgery, or cryotherapy, does not cure the underlying HPV infection. Currently, no treatment can do so.
Warts may heal and regrow. In other cases, the body may rid itself of the virus by destroying any remaining HPV cells after wart removal.
No over-the-counter wart removal product contains liquid nitrogen. Instead, they contain a mixture of dimethyl ether, propane, and sometimes isobutane.
Home freezing products may not be as effective as cryosurgery. Though they contain the same acids that doctors use, the acids are at much lower concentrations, and their freezing chemicals are also less powerful.
Home care products may be able to remove small warts, but they may only temporarily reduce the size or appearance of larger growths.
People sometimes use other methods, such as applying duct tape to the area for several weeks. However, these approaches have no or very slim scientific backing.
Most people experience minor pain during cryosurgery and a burning sensation when the skin thaws afterward.
During and immediately after the procedure, the treatment site may change color and swell. There may also be soreness for a few days.
About 24 hours after the procedure, a blister forms around the wart, and it resolves within 2 or 3 days.
The entire recovery typically takes around a week, and it is important to keep the area clean, dry, and free from friction or pressure throughout this time.
Any additional risks and complications depend on the type, size, and location of the wart.
Usually, plantar warts, large warts, and those in areas with a lot of pressure or friction tend to cause the most pain and complications, such as scarring or tissue damage.
- bleeding
- infection
- a prolonged healing process and the development of ulcers
- temporary nerve damage near the site
- a permanent loss in skin coloration
- scarring
- skin lesions that keep returning
- hair loss, according to one review
Dermatologists can reduce the risk of complications by limiting contact with liquid nitrogen to under 30 seconds.
Infection
A secondary infection developing in the site of cryosurgery is uncommon. The symptoms include:
- swelling
- pus or white, yellow, or brown fluid from the blister
- a fever
- increased, throbbing pain
- no signs of the area healing after a few days of care
Anyone with symptoms of a secondary infection should contact a doctor, who may prescribe a topical antiseptic or an oral antibiotic.
Many w arts disappear without treatment. It may also be possible to remove small warts with over-the-counter products.
If warts are large, numerous, or persistent, it may be best to have them professionally removed. This is particularly beneficial for people with certain chronic conditions or weakened immune systems.
To remove a wart, a dermatologist might use cryosurgery, or cryotherapy. This involves briefly applying liquid nitrogen to the skin. The healing period is about 1 week, and complications are rare, though they can occur.
Cryosurgery does not treat the underlying HPV infection that causes warts, and warts may regrow, in the same spot or elsewhere.
- Compound W Nitrofreeze
- Wartner Wart Removal Pen
- Dr. Scholl’s Freeze Away Wart Remover
Last medically reviewed on January 9, 2023
- Dermatology
- Complementary Medicine / Alternative Medicine
What are the signs that wart removal is successful?
Warts are harmless growths that often appear on the hands and feet. Some warts go away by themselves, but others may persist until a person gets treatment. People looking to remove warts can self-treat them at home or consult a doctor.
If a person has a weakened immune system or an underlying health condition, such as diabetes, they should check with their doctor before removing any warts.
This article looks at the different types of warts and the treatment options. It also explains how to know when wart treatment has been effective.
Warts are harmless skin growths that vary in appearance depending on their type. They can occur anywhere on the body but commonly affect the hands.
The human papillomavirus (HPV) causes warts, which can readily spread between people in close contact. If a person comes into contact with the virus, it can infect the surface layer of the skin, creating a wart. Having cuts or other damage to the skin makes this more likely to occur.
Some people have a higher likelihood of getting warts than others, including:
- children and young people
- people with a weakened immune system
- individuals with a skin condition that affects the skin barrier
As there are about 100 strains of HPV, the virus can cause many different types of warts. Types of warts include:
Common
Common warts have a rough, cauliflower-like texture and may appear as single warts or in a cluster. Their size ranges from 1 millimeter to more than 1 centimeter, and they usually occur on the backs of fingers or toes, around the nails, or on the knees.
Plantar
Plantar warts, which grow on the soles of the feet, look like calluses, have a hard surface, and contain small, black dots. They can appear as single warts or in clusters.
These warts may feel tender under pressure, and a person may feel as though they have pebbles in their shoes when walking.
Plane
Plane warts are flat, skin-colored warts that commonly grow on the face, hands, and shins. People usually have multiple plane warts. Shaving may be responsible for spreading the virus on the face or legs.
Filiform
Filiform warts look like threads or fronds coming from the skin. They appear on the face, particularly around the eyes, nose, or mouth, and usually grow quickly.
Butcher’s
Butcher’s warts look like common warts, and they can also appear on the hands, often as multiple warts. However, they occur due to a specific strain of HPV and affect people who live or work in cold, moist environments.
Wart treatments work by removing the wart rather than curing HPV. Due to this, warts may reoccur after treatment because the virus remains.
About two–thirds of warts resolve by themselves over 12–24 months, leaving no scarring or side effects.
However, if this is not the case, or a person wishes to remove warts quickly, various treatment options are available.
Salicylic acid
People can choose from many over-the-counter products containing salicylic acid that they can apply topically to a common wart. Daily treatment with salicylic acid removes warts within 12 weeks in 70% of cases.
Duct tape
There is no clear evidence that duct tape wart removal is effective and no guidance on how long it might take. The idea behind this approach is that applying new duct tape to a wart every few days may gradually remove layers of the wart.
A person can try this method easily at home, but it is important to note that it may not work and that some people may experience side effects, such as skin reactions and bleeding.
Cryotherapy
Cryotherapy uses liquid nitrogen to freeze the wart, which causes the surface layers to peel off.
People need regular treatments every 1–2 weeks to prevent the wart from growing back. After 3–4 months of treatment, cryotherapy effectively removes warts in about 70% of cases.
However, cryotherapy can cause blistering, which can last up to several days or weeks. It can also cause permanent white marks on the skin and may lead to temporary numbness in the treatment area.
Electrosurgery and curettage
Electrosurgery and curettage use heat to burn away the base of the wart. This type of treatment can treat large warts that have not responded to other treatments, but there are some downsides:
- The wound can take 2 weeks or more to heal.
- In 20% of cases, warts can reoccur.
- Electrosurgery and curettage can cause permanent scarring, which can be painful.
Other treatments
Other treatments for warts include:
- laser treatment, if other methods are not effective
- injection of bleomycin (Blenoxane)
- immunotherapy, such as imiquimod (Aldara), to encourage the immune system to fight the virus
How to get rid of warts
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 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
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.
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 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 the British 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.