Warts and verrucas

Published by Bupa's Health Information Team, February 2011.

This factsheet is for people who have warts or verrucas, or who would like information about them.

Warts are small, rough growths caused by the human papilloma virus (HPV). Any area of the skin can be affected, but warts are most commonly found on the hands, feet and face. Warts on the sole of the feet are known as verrucas and are also caused by HPV.

About warts and verrucas

Up to one in 10 people will have a wart at some point in their life, most commonly in childhood or adolescence. Warts and verrucas are usually harmless and go away by themselves, with up to nine in 10 disappearing within two years in children but often taking longer in adults.

Different types of warts vary in appearance and size, ranging from 1mm to 1cm. The following are some common examples of different types of wart.

Common wart (verruca vulgaris)

These are firm, raised growths with a rough surface, which might look like a very small cauliflower. They are most commonly found on the backs of your hands, fingers, toes and on your knees. 

Warts

Verruca (plantar wart)

These are usually found on the soles of your feet. They may have dark spots in the centre and may cause you pain when you put weight on them.

    Verruca

Plane wart (verruca plana)

These are round, smooth, flat growths often slightly brown in colour. They are common on your face and hands.

Mosaic wart

These are usually a number of verrucas packed together in a small area, often on your hands and feet.

Filiform wart

These are long, slender growths common on your face and neck.

Genital warts

These are usually caused by different types of HPV. They usually spread from other parts of the body, or most often, by sexual contact. You may feel irritation or soreness around the area. See your GP or go to a sexual health clinic for further advice.

Symptoms of warts and verrucas

Warts shouldn't usually cause you any symptoms, but you may find them uncomfortable or painful, especially if they are on your feet, genital areas or near your nail beds.

Most warts and verrucas go away by themselves but they can last two years or more. Contact your GP if your symptoms get worse or the wart becomes more painful.

Causes of warts and verrucas

Warts are caused by HPV, of which there are over 100 different types. Warts can be contagious, but the risk of you catching them is low. Warts usually spread from direct skin contact or in damp places, commonly in swimming pools and communal showers. If you scratch a wart, the viral particles may spread to other areas of your skin.

If you're a butcher, handle meat or work in an abattoir, you may be more likely to develop warts, although the reasons for this are unclear.

People who have a weakened immune system, such as those who have HIV/AIDS, or those who are taking medicines that suppress the immune system, are more likely to develop warts and verrucas.

Diagnosis of warts and verrucas

If you're worried about your wart or verruca, visit your GP. He or she will ask you about your symptoms and examine you. He or she may also ask you about your medical history. Your GP will try to diagnose which type of wart or verruca you have by its appearance.

Treatment of warts and verrucas

Most warts will go away by themselves and don’t need any treatment. Often leaving them is the best option, especially for children as some treatments can be painful and cause side-effects.

However, you may want to consider treatment if the wart becomes painful, unsightly or doesn’t go away after some time. Although this may help to clear your wart more quickly, there is no one treatment that is fully effective and little evidence to show which treatments work best.

If you have warts on your face, your GP will probably advise you not to treat these as it may lead to irritation or scarring.

If you're not sure whether your growth is a wart, see your GP.

Self-help

Although there isn’t much evidence to show that it works, you may wish to try placing duct tape over your wart as a way of getting rid of it. Cover the wart with duct tape for six days, then soak the wart in water and rub with an emery board or pumice stone to scrape off the dead skin. Keep the wart uncovered overnight and re-apply duct tape the next day. You may need to continue this cycle of treatment for up to two months before the wart disappears.

Medicines

There are many creams, gels and medicated plasters for treating warts, which you can buy at pharmacies. Many of these commonly contain an ingredient called salicylic acid (eg Bazuka gel). This is a chemical that acts slowly and helps by softening the hard outer layer of your wart. Soak your wart for five to 10 minutes and then follow the instructions on your medication. If you use this treatment, make sure you only apply it to the wart and try to get as little as possible on the surrounding area as it can cause irritation to your healthy skin. You may need to use this treatment for up to three months but don’t use it on your face without speaking to your GP or pharmacist first. If you suffer from eczema, you may find your skin is more sensitive to salicylic acid, but you can probably still use it on the soles of your feet.

Creams containing an ingredient called imiquimod can be applied to sensitive areas of the skin, like the face and genital areas, to get rid of warts. Imiquimod stimulates your immune system to recognise and attack the wart virus.

Creams containing retinoids, often prescribed to treat acne, can also be useful at treating warts. Some medicines with salicylic acid can contain podophyllotoxin. Don’t use retinoids or podophyllotoxin if you're pregnant, trying to get pregnant or breastfeeding.

Always read the patient information leaflet that comes with your medicine and if you have any questions, ask your pharmacist for advice.

Non-surgical treatments

Cryotherapy is the process of freezing your wart. Most commonly cryotherapy is usually done by your GP or a dermatologist (a doctor who specialises in identifying and treating skin conditions) using liquid nitrogen. The liquid nitrogen is applied to the wart using either a spray or applying it with a cotton bud. It will take between five and 30 seconds to freeze your wart depending on the technique used and the size and location of your wart.

Your GP may use over-the-counter sprays, for example, Wartner as a method of cryotherapy. However, liquid nitrogen can get up to three times as cold as over-the-counter sprays.

Cryotherapy may need to be repeated every three to four weeks. It can be painful and sometimes lead to blistering or scarring of the skin. It isn’t often recommended for children as it’s painful and they may not be able to stay still long enough for the procedure to be carried out. In certain circumstances, such as if your wart is over a tendon or you have poor circulation, cryotherapy may not be recommended. Cryotherapy to the sole of the foot can be painful and is not often used to treat verrucas.

Surgery

Surgical removal of warts or verrucas can't get rid of HPV, which causes them. It’s therefore unreliable in removing the infection, which means the warts can come back afterwards. Surgical removal may be recommended in certain circumstances, especially if your wart is stopping you from doing your daily activities. Your wart may be removed by scraping it away using an instrument called a curette, under local anaesthetic. This procedure can leave a raw or painful area and result in scarring.

If you have multiple or mosaic warts, or other treatments haven’t been successful, your GP may occasionally suggest laser treatment. This involves using a laser to destroy your wart and the blood vessels that supply it. There is very little evidence to show whether this treatment is effective, and it can also lead to pain and scarring.

Special considerations

If you have a condition that means your immune system is weakened, such as HIV infection or leukaemia, you're more likely to develop warts and they can be harder to treat. Under these circumstances warts have very occasionally developed into skin cancer. If your wart changes shape or colour, visit your GP.

Prevention of warts and verrucas

Warts and verrucas are usually caused by direct skin contact or contact with contaminated surfaces.

Taking the following precautions can help prevent warts and verrucas.

• Try not to touch other people’s warts.
• Don't share your towels, shoes or socks with someone who has a wart.
• Wear flip-flops in communal showers.
• Cover your wart with a plaster or glove.
• Don't scratch or pick your wart as it is more likely to spread.

There is no reason why you shouldn't take part in activities such as sports or swimming if you have a wart. It's a good idea to cover your wart with a plaster or if you go barefoot in communal areas, you may want to wear a verruca sock.

For answers to frequently asked questions on this topic, see Common questions.

For sources and links to further information, see Resources.