LEAFLETcryo

Warts, Verrucas and Cryotherapy

What are warts and verrucas?

• Warts are small rough lumps on the skin. They are caused by a virus (human papilloma virus) which causes a reaction in the skin. Warts can occur anywhere on the body but occur most commonly on hands and feet. They range in size from 1mm to over 1cm. Sometimes only one or two warts develop. Sometimes several occur in the same area of skin.
• Verrucas are warts that occur on the soles of the feet. They are the same as warts on any other part of the body. However, they may look flatter as they tend to get “trodden in”, and are sometimes painful if they press on a sensitive part of the foot. They are usually harmless, but may be unsightly.

Who gets warts and verrucas?

Most people develop one or more warts at some time in their life, usually before the age of 20. About 1 in 10 people in the UK have warts at any one time. Warts at the end of fingers may interfere with fine tasks.

Are warts contagious?

Yes, but the risk of passing them on to others is low. You need close skin-to-skin contact. You are more at risk of being infected if your skin is damaged, or if it is wet and in contact with roughened surfaces, for example, in swimming pools and communal washing areas.

You can also spread the wart virus to other areas of your body. For example, warts may spread round the nails, lips and surrounding skin if you put your hands and fingers near your mouth a lot. If you have a poor immune system you may develop lots of warts which are difficult to clear (for example, if you are on chemotherapy or have HIV/AIDS).

To reduce the chance of passing on warts to others:

• Don’t share towels.
• When swimming, cover any wart or verruca with a waterproof plaster.
• If you have a verruca, wear flip flops in communal shower rooms and don’t share shoes or socks.

To reduce the chance of warts spreading to other areas of your body:

• Don’t scratch warts.
• Don’t bite nails or suck fingers that have warts
• If you have a verruca, change your socks daily.

To treat or not to treat?

Warts and verrucas usually clear in time without treatment. There is no need to treat warts if they are not causing you any problems.

Cryotherapy (see below) is only used when other treatment options have failed. It is not suitable for children under the age of 12.

Without treatment, about 3 in 10 warts have gone within 10 weeks, and most warts will have gone within 1-2 years, and leave no scar. The chance that a wart will go is greatest in children and young people. Sometimes warts last longer. In particular, warts in older people are sometimes more persistent and may last for several years. Treatment can often clear warts more quickly. However, treatments are time consuming and some can be painful. Parents frequently want treatment for their children, but children are often not bothered by warts. In most cases, simply waiting for them to go is usually the best thing to do.

What are the treatment options?

The three most commonly used treatments are:

• Salicylic acid
• Covering with duct tape
• Freezing or liquid nitrogen treatment.

Salicylic acid

There are various lotions, paints and special plasters that contain salicylic acid. You can buy these over the counter at pharmacies and chemists, or your doctor may prescribe one. Read the instructions in the packet on how to use the brand you buy or are prescribed, or ask your pharmacist for advice. Usually:

• You need to apply each day for three months. This acid “burns” off the top layer.
• Every few days rub off the dead tissue from the top of the wart/verruca with emery paper (card-based nail file, not the metal ones). Gradually the wart is “burnt off” and “rubbed away”.
• It is best if you soak the wart/verruca in water for 5-10 minutes before applying the acid.
• You should not apply acid to the face because of the risk of skin irritation which may cause scarring.
• If you have diabetes or poor circulation, you should use salicylic acid only on the advice of a doctor.

If you put the acid on correctly each day you have a good chance of clearing the warts/verrucas within three months. Studies report that about 75% of warts and verrucas are cleared within three months with daily use of salicylic acid. Tips for success include:

• Try not to get the acid on the skin next to the wart/verruca as it may become irritated. You can protect the nearby skin by putting some Vaseline on the normal skin beforehand, or by putting on a plaster with a hole in it which just exposes the treatment area.
• If the surrounding skin does become sore, stop the treatment for a few days until it settles. Then re-start treatment. There is also a small risk that you may get a skin allergy to the treatment. If this occurs, the surrounding skin becomes red and itchy.
• It may take two weeks or more before you notice any improvement. It can take up to three months of daily applications for the warts/verrucas to go completely.
• Treatment may work better if you put a plaster on the area after applying the acid.
• Acid lotions and paints are flammable. Keep them away from open fires and flames.

Duct tape

Studies have found that covering a wart/verruca with strong adhesive tape is likely to clear the lesion within a month or two. In the studies about 70% of warts had cleared within this time frame. It may be worth a try as it is painless. Further studies are needed however to clarify the role of this treatment. The method described was:

• The wart/verruca was covered with duct tape for six days. If the tape fell off during this time a fresh piece of tape was put on.
• After six days the tape was removed and the wart soaked in warm water for five minutes. After drying it was then gently rubbed with an emery board or pumice stone to get rid of dead tissue from the top.
• The wart was then left uncovered overnight and duct tape put on again the next day.
• This treatment was continued for up to two months. (Note: most warts that cleared with duct tape did so within 28 days.)

You should not use duct tape on the face as it can sometimes irritate the skin.

Cryotherapy or liquid nitrogen treatment

Warts, veruccas, skin tags, small fleshy growths and similar small “lumps and bumps” on the skin are ideal for liquid nitrogen treatment. Cryotherapy is only considered if you have used other treatment options for a minimum of three months and have not been successful. It is never used in children under the age of 12.

Liquid nitrogen is extremely cold and will freeze any living tissue it comes into contact with. The freezing and thawing destroys the wart/verruca tissue. There is an option to buy a very cold spray (dimethyl-ether/propane spray) from pharmacies. You can apply this yourself but you should never treat warts on your face with this.

Is it painful?

The nitrogen is sprayed on or applied to the area. Applications usually last about 10-30 seconds. Try holding a cube of ice against your skin for 10-30 seconds. It is uncomfortable but usually not too painful. Liquid nitrogen applied to skin is similar but colder and most people find the discomfort quite bearable. Occasionally a small blister (sometimes a blood blister) develops for a day or so on the nearby skin after treatment. If this happens it is best to pop it with a clean pin and apply a plaster. Also, there is a slight risk of scarring the nearby skin or nail, or damaging underlying tissues such as tendons or nerves. It is not suitable for children under 12 or people with poor circulation.

What can I expect?

After a treatment the lump, wart or whatever is being treated will gradually discolour and fall off. The surrounding skin will sometimes become red and swollen and be sore for a day or so. It is similar to a mild burn. To clear the wart/verruca/lesion fully it can need up to four treatment sessions over a period of a few weeks to get to the root. Each treatment session is a couple of weeks or so apart. The chance of clearing a wart/verruca with freezing treatment is about the same as acid treatment.

Other treatment options:

A podiatrist or chiropodist can pare or rub down a verruca. This is often enough to ease any pain, even though part of the verruca may still remain.

If the above treatment options do not clear warts/verrucas/other lumps and bumps – then other methods may be tried. There are various other options but they are usually only done by specialists if other treatments have failed. Some treatments (such as laser treatment) are not available on the NHS to treat warts and verrucas.