This page was written and supervised by a specialist physician at IC Clinic.

A Complete Guide to Wart Treatment

Wart Treatments Covered by Health Insurance

“How are warts treated?” “Is wart treatment covered by insurance?” “Where can I find a good clinic?”

If you have these questions, you are not alone.

Because there are many different types of warts, choosing the right treatment for your specific type is important.

Leaving warts untreated or attempting to remove them yourself carries a risk of making the condition worse — please avoid doing either.

In this article, we explain what warts are as a condition and describe the four main treatment options available.

We also cover what to expect during treatment, costs, and other common concerns, so we hope you will read through to the end.

What Are Warts? 4 Key Facts

A wart is a small raised growth on the skin, known medically as a “verruca” (疣贅, yuusei).

Warts can be difficult to distinguish from corns or calluses; however, viral warts typically show small black dots in the raised area due to the proliferation of capillaries.

Viral warts can spread to other parts of the body, so early treatment is advisable.

Below we explain the basics of warts — their causes, types, and what kind of condition they are.

(1) Warts Are Caused by Viral Infection, Aging, or UV Exposure

	Viral Warts	Seborrheic Keratosis (Age-Related Warts)
Cause	・Human papillomavirus (HPV) ・Molluscum contagiosum virus	・Cumulative UV damage over the years ・Skin aging due to getting older ・Friction from clothing
Appearance	・Color varies: skin-toned, light pink, dark brown, etc. ・Size ranges from 1 mm to several centimeters	・Brown or dark brown in color ・A few millimeters to 2–3 cm in size

Most viral warts are caused by infection with the human papillomavirus (HPV). There are many strains of HPV, and the location and shape of warts vary depending on which strain is involved.

Another type of viral wart is caused by the molluscum contagiosum virus. Commonly known as “water warts” (molluscum contagiosum), these are a skin infection seen most often in children.

Age-related warts (seborrheic keratosis) develop due to skin aging, cumulative UV damage, and friction from clothing or accessories. Despite the name “age-related,” they can appear in people in their 20s as well.

(2) There Are Many Different Types of Warts

Warts can be further classified into various types, each differing in appearance, presence of pain, and location on the body.

Below we introduce the characteristics of each type.

For more detailed information, please also see our page “Types of Warts and Their Treatments.”

Verruca Vulgaris (Common Wart)

Verruca vulgaris is considered the most common type of viral wart and includes filiform warts and mosaic warts. Filiform warts often form thin, thread-like projections on the face and neck. Mosaic warts are warts that have merged together to form a cobblestone-like pattern.

They are found most often on the palms and soles, tend not to protrude much, and have a rough surface. Black dots or a core-like appearance may be visible in the raised area due to capillary proliferation.

Seborrheic Keratosis (Age-Related Wart)

Seborrheic keratosis is a raised, brown or black spot-like wart that commonly appears on the face of middle-aged and older adults. It is also called an “age wart.”

It is thought to be caused by aging and UV exposure, typically beginning in people in their 30s–40s and seen in most people over the age of 60.

It commonly appears on the face, temples, and sun-exposed areas such as the chest. CO2 laser treatment tends to be highly effective for this type.

Acrochordon (Skin Tags on the Neck, Underarms, or Chest)

Acrochordons are small, brownish warts measuring 1–2 mm that typically form in areas subject to friction from clothing, such as the neck and underarms.

They tend to appear from around age 30 and often develop in large numbers. They can become inflamed from rubbing against clothing or catching on necklaces.

When they appear in large numbers and aesthetic concerns are a factor, CO2 laser treatment is a highly suitable option.

Flat Wart (Verruca Plana)

Flat warts (verruca plana) are viral warts that are brownish and flat in shape.

They tend to cluster together in large numbers and are more likely to appear on the foreheads, backs of the hands, and arms of relatively young people.

Because they are small and brownish, they are sometimes mistaken for pigmented spots.

Pigmented Wart

A pigmented wart is a viral wart associated with black pigmentation.

It is also known as a “black wart.”

Myrmecia

Myrmecia is a firm, raised viral wart commonly found on the palms and soles of children.

The center is often sunken, which can lead to it being mistaken for a corn. If the lesion progresses deeper into the skin, it may cause significant pain.

Treatment often takes considerable time, and these warts can be difficult to resolve.

Punctate Wart

Punctate warts are small, rough viral warts that appear in large numbers on the soles of the feet.

They are often white in color.

(3) Warts Can Spread to Others

Viral warts can be transmitted from person to person through direct skin contact, so care is needed. They can also spread to other areas of your own body.

For example, touching a wart and then touching another part of your body may cause a new wart to develop there.

The virus does not easily infect healthy, intact skin or mucous membranes, so there is no need for excessive worry. However, the risk of viral entry increases if there are small cuts in the skin or mucosa, or if immunity is reduced.

Non-viral age-related warts, on the other hand, do not generally spread.

(4) Warts May Resolve on Their Own in Some Cases

Viral warts may disappear naturally once immunity develops. However, waiting for them to resolve on their own carries a risk of worsening, so seeking medical treatment is generally recommended.

It can take months or even years to develop immunity, during which time warts can continue to grow and multiply. They may spread to other areas while partly resolving, or become larger and cause discomfort.

For these reasons, we recommend seeking treatment early rather than waiting for warts to go away on their own.

【Important】What Should You Avoid Doing with Warts?

There are two things you should never do when you have a wart: leaving it untreated and trying to remove it yourself.

Both carry a risk of making the wart worse. In particular, viral warts can spread to other parts of the body, so please avoid touching them.

Most warts are benign, but in rare cases they may be malignant, so if you notice a wart, please see a doctor promptly.

Below we explain in detail the two things to avoid when you have a wart.

Leaving a Wart Untreated

If left untreated, warts may spread to other areas or grow larger.

For example, touching a viral wart and then touching your foot may cause a new wart to form there. There is also a risk of unknowingly passing the virus on to others.

In addition, even a small wart can gradually grow as the virus continues to multiply over time.

Larger warts and multiple warts often require prolonged treatment, so it is important not to leave a wart untreated and to start treatment as early as possible.

Trying to Remove a Wart Yourself

Attempting to remove a wart yourself may make the condition worse.

In particular, please never try to forcibly remove a wart using scissors, tweezers, or similar tools. Doing so risks bleeding and bacterial infection, which can worsen the condition.

Even over-the-counter products marketed for warts do not address the root cause easily. This is because there are many types of warts, and it is difficult to identify your type correctly and choose the right treatment on your own.

Even for small warts, please do not try to remove them yourself. Instead, visit a medical institution to have the type of wart properly assessed and treated accordingly.

Four Main Wart Treatment Options

There are four main treatment options for warts, each differing in insurance coverage eligibility and downtime.

Below is an overview of the typical costs, advantages, and disadvantages of each treatment.

We will go on to explain each treatment option in detail.

Treatment Option 1: Cryotherapy with Liquid Nitrogen

Cryotherapy using liquid nitrogen is one of the most common treatments for warts.

It works by applying liquid nitrogen to the wart to induce frostbite, which destroys the abnormal tissue on the skin surface.

Specifically, the wart is frozen using liquid nitrogen at −196°C. After treatment, the infected skin necrotizes and peels away along with the wart.
※ Please note that our clinic places limits on the number of warts that can be treated per session.

This is our clinic’s first-line treatment for warts, typically performed once a week and continued for approximately two months.

If improvement is not seen, we will promptly consider switching to or adding another treatment approach.

Treatment Option 2: Surgical Excision

This involves using a scalpel under local anesthesia to surgically remove the wart completely. It is considered as an option for warts that are difficult to treat by other means.

Because local anesthesia is used, there is no pain during the procedure itself; however, the anesthetic injection may be uncomfortable depending on the location, which means some sites are not well suited to this approach.

Treatment Option 3: CO2 Laser Treatment

The CO2 laser emits a laser beam that is absorbed by water and converted into heat.

CO2 laser irradiation can significantly reduce the volume of a wart and is mainly used when the goal is to reduce the size of a large wart.

Because local anesthesia is used, there is no pain during the procedure; however, the anesthetic injection itself may be uncomfortable depending on the location, which means some sites are not well suited to this approach.

＊CO2 laser treatment is not covered by health insurance.

Treatment Option 4: Adjunctive Medications

This involves using topical treatments or herbal (Kampo) medicines that have an effect on warts. It is often combined with other treatments.

This approach is also suitable for patients who are sensitive to pain or for treating warts in children.

If you are unsure which wart treatment is right for you, please consult IC Clinic.

It is natural to feel uncertain about which clinic or treatment to choose given the costs and expected outcomes involved.

IC Clinic is equipped to provide all of the treatment options introduced here. This means we can address a wide range of wart types and work with each patient to select the most appropriate treatment.

Drawing on our expertise in dermatology and skin care, we strive to treat warts while minimizing the risk of scarring.

Even if you have a small wart and are unsure whether to seek treatment, please feel free to come in for a consultation.

4 Points to Be Aware of with Liquid Nitrogen Wart Treatment

In Japan, cryotherapy with liquid nitrogen is the most commonly used wart treatment; however, it does have its limitations.

Because liquid nitrogen is used at so many clinics, some patients may have the impression that it is the only available wart treatment.

However, cryotherapy with liquid nitrogen is not always the most suitable wart treatment in every situation.

In fact, many patients come to our clinic after years of cryotherapy for viral warts at other facilities without achieving a complete resolution.

While liquid nitrogen is a common approach to wart treatment, it is important to understand that it has both advantages and disadvantages.

Below we outline four points to keep in mind regarding liquid nitrogen wart treatment.

(1) Many Patients Find Liquid Nitrogen Treatment Painful

Cryotherapy can be quite painful, and for patients who are sensitive to pain — such as children — it may become difficult to continue treatment.

Treatment is typically repeated every 1–2 weeks for several sessions, sometimes more than 10 times in total, and without consistent attendance the treatment may not be sufficiently effective. Regular visits are therefore essential for a good outcome.

The pain following liquid nitrogen treatment usually lasts about 1–2 days, and pain relief medication can be taken to help manage it.

At our clinic, cryotherapy remains our first-line treatment for warts; however, for patients who find the pain very difficult to tolerate, we will discuss options such as pain reduction measures or alternative treatments.

Blood blisters or water blisters may also develop after liquid nitrogen treatment. If a blister breaks, it is important to disinfect the area and protect it with a gauze dressing to prevent infection.

(2) Worsening After Liquid Nitrogen Treatment Is Possible in Some Cases

After cryotherapy, small new warts may sometimes appear around the treated area.

This can happen because when a viral wart is treated with liquid nitrogen, the cells are disrupted and the virus responsible for the wart can be scattered to the surrounding area.

The virus does not penetrate normal, intact skin, so new warts tend to form only where the surrounding skin has small wounds.

Although this is uncommon, it is worth knowing that in some patients, cryotherapy may be followed by the spread of what was initially a small wart.

(3) Liquid Nitrogen Treatment Can Sometimes Lead to Prolonged Treatment Duration

Liquid nitrogen treatment rarely resolves a wart in a single session, and the overall treatment period can become lengthy.

Treatment is performed every 1–2 weeks, and some patients see resolution in as few as 2 or 3 sessions.

However, cryotherapy can sometimes cause the skin to become firm and thickened, which may actually make the wart harder to treat. This means treatment can take considerably longer for some patients.

There is significant individual variation in how long liquid nitrogen treatment takes, and it is difficult to predict in advance.

(4) Post-Inflammatory Pigmentation May Remain After Liquid Nitrogen Treatment

Cryotherapy is very commonly associated with post-inflammatory hyperpigmentation (dark spots). This is a side effect seen in approximately 90% of patients who undergo liquid nitrogen treatment.

Pigmentation typically appears around one month after the wart has been removed and may take six months to a year to fade. In some cases, it can remain slightly larger than the original wart.

For this reason, our clinic recommends considering alternative treatments such as laser therapy — rather than cryotherapy — when pigmentation is a concern, or when multiple small warts are present in visible areas such as the face or neck.

IC Clinic’s Approach to Wart Treatment

• 1. Team-Based Treatment Drawing on a Broad Range of Expertise

Our dermatologists and plastic surgeons work as a team to provide wart treatment, enabling a high standard of clinical care.

• 2. Results-Focused Treatment Aimed at Resolution in the Shortest Time

With surgeons on staff, we are able to offer surgical and other definitive treatment options when long-term treatment is anticipated — for example, in difficult-to-treat cases. When desired, we can move to the next stage of treatment promptly.

• 3. A Wide Range of Treatment Options to Choose From

In addition to standard cryotherapy with liquid nitrogen, we also offer surgical excision and CO2 laser treatment. This allows us to select the approach that best suits each individual patient.

• 4. Health Insurance Coverage to Help Reduce Out-of-Pocket Costs

Our clinic offers wart treatments covered by national health insurance, helping to keep costs manageable. We take time in our pre-treatment consultations to listen carefully to your concerns and goals, and recommend a plan that is genuinely suited to your needs.

• 5. Conveniently Located for Easy Access

IC Clinic is located just a short walk from major train stations, making it easy to attend follow-up appointments. We welcome patients from Tokyo, Chiba, Kanagawa, and beyond, in addition to Saitama.

How Wart Treatment Proceeds at IC Clinic

Here is an overview of what to expect during wart treatment at IC Clinic.

The following outlines the typical treatment process at IC Clinic.

1. Assessment of wart type and condition
2. Liquid nitrogen treatment
3. Proposal of the next treatment step
4. Consideration of surgical options
5. Proposal of CO2 laser treatment

Let us look at each step in more detail.

STEP 1: Assessment of Wart Type and Condition

First, we assess the type of wart and, in most cases, begin treatment with cryotherapy as the first-line option.

STEP 2: Liquid Nitrogen Treatment (up to approx. 2 months)

During liquid nitrogen treatment, patients visit once every 1–2 weeks and continue treatment for approximately 2 months.
※ To minimize skin damage from frostbite, we limit each session to approximately 10 minutes of treatment time.

STEP 3: Proposal of the Next Treatment Step

If there is no improvement after two months of cryotherapy, we promptly consider and propose the next stage of treatment based on the patient’s wishes.

STEP 4: Consideration of Surgical Options

When the number of warts is relatively limited, surgical excision may be a good option and is covered by health insurance; however, the number of warts that can be treated in a single session is limited.

STEP 5: Proposal of CO2 Laser Treatment

When warts are widespread and difficult to treat, CO2 laser treatment is also an effective option.
While this treatment is not covered by health insurance, there is no limit to the number of warts that can be treated.

＊In conjunction with the above treatments, supplementary therapies such as oral or topical medications may be added as needed.

Wart Treatment Fees at IC Clinic

Below is a summary of the estimated fees for wart treatments at IC Clinic.

Approximate Treatment Fees

Cryotherapy with Liquid Nitrogen

1–3 warts: approx. ¥630 (at 30% patient co-payment) ※ Consultation and prescription fees are charged separately.
4 or more warts: approx. ¥810 (at 30% patient co-payment) ※ Consultation and prescription fees are charged separately.

Surgical Excision

Exposed areas: approx. ¥5,000 (at 30% patient co-payment) ※ Consultation and prescription fees are charged separately.
Non-exposed areas: approx. ¥5,000 (at 30% patient co-payment) ※ Consultation and prescription fees are charged separately.
※ Pathological examination is performed as a rule at the physician’s discretion.
※ In addition to the surgery fee above, please allow approximately ¥1,000 for consultation and prescription fees, and approximately ¥3,000 for testing and pathological examination fees.

CO2 Laser Treatment

This treatment is not covered by health insurance. Please consult one of our physicians for further details.

Fees vary depending on the condition of the warts. If you would like a specific quote, please do not hesitate to contact us.

Private Medical Insurance May Also Apply to Wart Treatment

If you have private medical insurance or are a member of a mutual aid association, you may be eligible to receive a surgical benefit payment when you undergo a surgically covered wart procedure after being seen by a physician.

Please note that even if you hold private insurance, you will need to submit the claim yourself to receive benefits.

If a physician’s certificate is required, please inform us at the time of your visit.

Please check with your insurance provider or mutual aid association to confirm whether wart treatment qualifies for benefit payments.
(The procedure name used may be “皮膚皮下腫瘍摘出術” — Excision of Skin and Subcutaneous Tumor, or similar.)

Frequently Asked Questions About Warts

Below we address some of the most common questions and concerns about warts. If you have any questions, we hope you will find this section helpful.

For Wart Treatment, Please Consult IC Clinic

If you are considering wart treatment, please consult IC Clinic.

Our clinic offers four wart treatment options: cryotherapy with liquid nitrogen, surgical excision, CO2 laser treatment, and adjunctive therapies, allowing us to recommend the approach best suited to each individual patient.

All of our locations are conveniently situated close to train stations, making it easy to attend the multiple appointments that wart treatment often requires. We are open every day including weekends and public holidays, so you can visit at a time that fits your schedule.

If you are concerned about warts, please do not hesitate to consult IC Clinic.

Four Key Features of IC Clinic

(1) Results-Focused Specialist Treatment

Our team of specialist physicians with extensive clinical experience is committed to results-focused treatment that minimizes the burden on each patient.

(2) Treatment Plans Tailored to Your Symptoms and Wishes

We listen attentively to each patient’s concerns and anxieties and provide a treatment plan that genuinely suits their individual needs.

(3) Minimizing Discomfort and Scarring

From our wide range of treatment options, we select approaches that aim to minimize discomfort during and after the procedure, keeping any lasting effects to a minimum.

(4) A Welcoming Clinic for Patients of All Ages and Backgrounds

We create a clinic environment where anyone — regardless of age or gender — can feel comfortable seeking a consultation.

Self-Pay Wart Treatment | Wart Treatment in Practice

Cryotherapy with Liquid Nitrogen: The Most Widely Used Wart Treatment

In Japan, cryotherapy with liquid nitrogen is the most commonly used wart treatment. Some patients may even have the impression that it is the only available option.

Among wart treatments, cryotherapy is straightforward, requires no complex technique, and is simple to administer — and it is said that close to half of all warts respond to cryotherapy alone.

That said, cryotherapy with liquid nitrogen is not always the most suitable approach. Many patients visit our clinic having undergone years of cryotherapy elsewhere without achieving full resolution.

Limitations of Cryotherapy for Wart Treatment

Cryotherapy with liquid nitrogen is generally considered to have the following limitations.

1

Cryotherapy can be quite painful, and patients who are sensitive to pain — such as children — often find it difficult to continue treatment. Because cryotherapy must be performed regularly, patients who cannot attend consistently may not achieve sufficient results.

2

Cryotherapy can disperse the virus responsible for warts to the surrounding area, potentially spreading the affected zone. It is not uncommon for patients to report that warts that were originally small spread after undergoing cryotherapy.

3

Cryotherapy can cause the skin to become firm and thickened, which may actually make the wart more resistant to treatment.

4

Cryotherapy is very commonly associated with post-inflammatory pigmentation. For this reason, when pigmentation is a concern, or when multiple small warts are present in visible areas such as the face or neck, alternative treatments such as laser therapy may be more appropriate than cryotherapy.

Conditions That Resemble Warts

• Mole (Nevus)

This refers to a pigmented nevus. It typically occurs as a single lesion and may be raised. If it catches on things and bleeds, or shows signs of enlargement that warrant investigation, surgical treatment may be a suitable option.

• Dermatofibroma

This can resemble a wart and commonly appears on the limbs. It is a firm, dark brown to black skin tumor. It may develop as a result of an insect bite or minor injury.

• Neurofibroma

A benign skin tumor arising from peripheral nerves. It is also known to occur in large numbers in neurofibromatosis type 1 (von Recklinghausen disease). It can also appear as a solitary lesion, in which case it may need to be distinguished from a Miescher nevus.

• Soft Fibroma (Acrochordon / Skin Tag)

Commonly found in areas subject to friction, such as the neck, underarms, and groin. It appears as a skin-colored, wart-like protrusion. The number increases gradually with age and friction. Small ones that appear around the neck are sometimes called acrochordons.

• Basal Cell Carcinoma

The most common type of skin cancer, which frequently develops on the face. It can resemble a wart, so careful differentiation — including skin biopsy when appropriate — is important. Complete surgical excision is required, and in some cases referral to a general hospital or university hospital may be necessary.

• Malignant Melanoma

A form of skin cancer that can metastasize and may be life-threatening. Prompt treatment upon detection is important. It most commonly occurs on the soles of the feet. If diagnosed, we will promptly refer the patient to a university hospital or cancer center.

Wart Treatment | CO2 Laser Treatment

The CO2 laser emits a laser beam that is absorbed by water and converted into heat. CO2 laser irradiation can significantly reduce the volume of a wart and is mainly used when the goal is to reduce the size of a large wart. Because local anesthesia is used, there is no pain during the procedure; however, the anesthetic injection itself may be uncomfortable depending on the location, which means some sites are not well suited to this approach.

＊CO2 laser treatment is not covered by health insurance.

Wart Treatment at IC Clinic

Although not covered by health insurance, CO2 laser treatment can serve as a first-line option in certain cases. It can often be completed in a single session and causes minimal damage to the surrounding tissue. It is also an effective approach for widespread, difficult-to-treat warts.

＊In conjunction with the above treatments, supplementary therapies such as oral or topical medications may be added as needed.

Q&A About Wart Treatment

Why do warts develop?

Warts develop when a type of virus called human papillomavirus (HPV) infects the skin. Transmission can occur through direct person-to-person contact, or indirectly via swimming pools, foot-drying mats, slippers, and similar items. The incubation period is 1–6 months and is often quite long, which makes it difficult to identify the source of infection. There are many strains of HPV, and the strain determines which type of wart develops. In addition to common warts, flat warts (verruca plana), condylomata acuminata, and Bowenoid papulosis are also caused by HPV infection.

Is wart treatment covered by health insurance?

Health insurance coverage applies in the following cases:

• When the possibility of skin cancer cannot be ruled out
• When the wart is on the eyelid and obstructing vision
• When the wart catches when shaving or getting dressed
• When the wart is large and requires surgical excision
• When a viral wart is suspected and treatment is required

Some treatments — such as CO2 laser treatment for cosmetic purposes — are not covered by health insurance.

I have been undergoing liquid nitrogen cryotherapy for a year but my warts are not improving. Is full resolution possible?

Please do not hesitate to consult us. Warts often do not respond to liquid nitrogen treatment alone, so selecting the most appropriate treatment based on your individual situation is important. At IC Clinic, we take into account the type of wart and the characteristics of each treatment, and we can promptly transition to a more suitable approach — based on your preferences — for patients whose warts are not responding well. We particularly encourage patients who have tried liquid nitrogen treatment elsewhere without satisfactory results to come in and explore their options with us.

Is wart treatment painful?

This depends on the type of treatment. CO2 laser treatment involves a brief amount of discomfort when local anesthetic is injected into the wart area, but there is no pain during the procedure itself. Other treatments involve minimal discomfort.

How long does wart treatment take?

This varies depending on each patient’s situation, so it is difficult to give a specific number of months or sessions. For typical warts, many patients who come in weekly see resolution within about 2–3 months.

Can warts develop into cancer?

It is well established that HPV infection — the cause of warts — can contribute to certain cancers such as cervical cancer. More than 100 strains of HPV have been identified, and the strains with oncogenic potential are largely known. For the strains typically responsible for common warts, the risk of cancer development is considered very low, so please do not be overly alarmed. However, Bowenoid papulosis and condylomata acuminata may involve strains with higher oncogenic potential, so it is important to ensure these are fully treated.

Can seborrheic keratosis (age-related warts) develop into cancer?

There are currently no reports of skin cancer arising from seborrheic keratosis, so there is generally no need for significant concern. That said, some skin cancers can look very similar to seborrheic keratosis. If you are worried, we recommend coming in for an examination.

For seborrheic keratosis, which is better — liquid nitrogen or CO2 laser treatment?

For aesthetically pleasing results, laser treatment is generally the preferred option (not covered by health insurance).

I have been told I have skin tags on my neck. Can they be removed?

Removal is possible using CO2 laser treatment at our clinic. Please note that CO2 laser treatment is not covered by health insurance.

Are there any lifestyle precautions during or after wart treatment?

There are no particular restrictions, so you can continue with your normal daily activities. However, please be aware that scratching at warts with fingernails can spread the virus and cause new warts to appear in other areas.

I am worried about passing my wart on to family members. What should I do?

Warts do not spread easily to other people, so there is no need for excessive concern. That said, measures such as avoiding direct contact with the wart and using separate towels for hands and feet are helpful precautions to take.