Cryotherapy for Warts and Verrucae

What is a wart or verruca?

Warts and verrucae are small growths on the skin caused by human papilloma virus (HPV). You may have heard of HPV in other contexts – but there are many different types of this virus. The different sub-types all behave differently and can affect different parts of the body. It is subtypes 2 and 4 that most commonly cause verrucae.

What is the difference between a wart and a verruca?

The only difference between a wart and a verruca is the location: verrucae are warts on the soles of the feet.

Do I have to have my wart or verruca removed?

Whilst warts and verrucae may cause discomfort and not be vey nice to have, they should not cause any medical problems in healthy individuals. Warts and verrucae are usually harmless and go away by themselves without treatment. In children, about two-thirds disappear within two years. Some disappear much quicker than this – within a few months. It may take up to five to 10 years for warts and verrucae to clear up in adults. 

Therefore, having a wart or verruca does not mean that you have to have it removed. It is a personal choice. Some people chose to remove warts or verrucae because they can spread to other areas – such as neighbouring fingers or elsewhere on the feet, they are worried about other people catching them (when swimming for example) or they just don’t like the way they look.

What is the best treatment for my wart or verruca?

Most people will try to treat their wart or verruca at home before seeking help from a medical professional.  You can buy over the counter creams that contain salicylic acid or home-freezing kits.  The home freezing kits are different from the freezing that we do in a medical clinic.  Your doctor or nurse will use liquid nitrogen to freeze your wart or verruca, whereas over the counter preparations do not use liquid nitrogen.  Liquid nitrogen should only ever be used by a medical professional.

What types of warts can be treated by freezing?

Most warts can be treated using cryotherapy. Research suggests that cryotherapy may be particularly effective in treating warts of the hand, even when compared to traditional topical creams. Cryotherapy may also be helpful in treating plantar warts on feet (verrucae).  We can also treat other skin lesions such as skin tags and seborrheic keratoses with cryotherapy.

Who’s a good candidate for this type of treatment?

You may be a good candidate if over-the-counter treatments like salicylic acid creams or home-freezing haven’t successfully treated your warts. Cryotherapy may also be a good option if you want to quickly treat your wart.

People who are sensitive to pain, such as young children and the elderly, may have difficulty with the procedure as it does sting/burn.

How should I prepare for my cryotherapy appointment?

Prior to your appointment, it is important that you file the surface of your wart or verruca with a nail file or pumice stone (that you should then discard as it will potentially spread the HPV virus to other areas if you use it again). Then soak the area for about 15 minutes to soften the wart. This will make sure that freezing has the best chance of success.

What happens during this procedure?

During the procedure, your doctor or nurse may scrape away the surface of your wart or verruca first. Then they will apply the freezing substance (liquid nitrogen) with a spray. 

Cryotherapy may cause discomfort. We don’t tend to inject local anaesthetic though as the treatment is only for a few seconds at a time. For larger warts and verrucae, you may need follow-up sessions to reapply cryotherapy.

What should I do after the treatment?

You may have some pain for up to three days following the procedure. You should be fully recovered within two weeks.

There’s a chance for minimal scarring. You may also develop a blister over the site of the wart. If the blister breaks, clean the area with an antiseptic wipe. This will minimise the spread of virus from the wart.

In most cases, the blister and wart will disappear within a few days. If the blister is still giving you pain or still contains fluid after this, call your doctor for a review.

We may advise that you continue with home treatment after cryotherapy – such as applying salicylic acid or applying duct tape – but your clinician will advise you about this at the time of your treatment.

How effective is this treatment?

There’s limited research on the effectiveness of cryotherapy for the treatment of warts.

A study from 2002 found that duct tape occlusion therapy was more effective at treating the common wart than cryotherapy. According to the study, cryotherapy successfully treated warts in 60 % of participants. Duct tape occlusion therapy was successful for 85 % of people.

Are there any complications?

Cryotherapy for warts is generally safe, but it has some risks. The biggest possible complication is infection of the wound, usually by bacteria. Symptoms include:

• increased swelling
• throbbing pain
• fever
• yellow discharge
• pus

Bacterial infections can be treated using oral antibiotics.

Some other possible complications of cryotherapy include:

• damage to your nerves, which can lead to temporary numbness
• slow healing
• ulcer formation
• long-lasting scar or altered pigmentation
• Recurrence after treatment
• The need for further treatments

Your clinician will go through everything with you in your appointment and you will have the opportunity to ask questions and highlight any concerns you may have.