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Warts and verrucas


Warts are small, rough lumps on the skin that are benign (non cancerous). They often appear on the hands and feet.

Warts can look different depending on where they are on the body and how thick the skin is. A wart on the sole of the foot is called a verruca. The clinical name for a verruca is a plantar wart.

Warts are caused by an infection with a virus called human papilloma virus (HPV). HPV causes keratin, a hard protein in the top layer of the skin (the epidermis), to grow too much, producing the rough hard texture of a wart.

Types of warts

There are several different types of warts. The more common types include:

  • common warts
  • plantar warts (verrucas)
  • plane warts
  • filiform warts
  • periungual warts 
  • mosaic warts

The appearance of each type of wart will depend on several factors:

  • where it is located on your body
  • the strain (type) of HPV that is responsible for the wart
  • factors such as whether you have a weakened immune system
  • whether you have rubbed or knocked the wart

See Warts and verrucas - symptoms for more information about each type of wart.

Who gets warts

Most people will have warts at some time during their life. However, they are more common in school children and teenagers than in adults. Research has indicated that 4-5% of children and adolescents in the UK have warts.

Warts are uncommon in babies and occur in equal numbers between males and females.

People who have an increased risk of developing warts include those with weak immune systems, for example, following treatment for cancer or due to an illness such as HIV and AIDS, and those who have had an organ transplant. Around 50% of people who have had a kidney transplant develop warts within five years.

A type of wart that is known as a ‘butcher's wart’ can sometimes develop on the hands of people who are regularly in contact with raw meat, fish or poultry for long periods of time. However, this type of wart is rare.

Genital warts

Like other types of warts, genital warts are caused by HPV. Genital warts are most commonly transmitted during sexual intercourse and other types of sexual activity, including oral sex.

Genital warts should not be treated at home using over-the-counter medicines. If you think you have genital warts, visit your GP or local sexual health clinic.

See the A-Z topic about Genital warts for more information and advice.


Most warts disappear on their own without treatment, although treatment can help to get rid of them more quickly. Treatment may be recommended in cases where:

  • the wart is causing you pain or distress
  • there are associated risk factors, such as having a weakened immune system

Several treatment options are available to help treat warts and verrucas successfully. See Warts and verrucas - treatment for more information.

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Warts can be different sizes, ranging from 1mm to over 1cm. Warts are not usually painful, although those that develop under your fingernails (periungual warts) or on the soles of your feet (verrucas) can sometimes hurt. Warts can also occasionally itch or bleed.

You may only have only one or two warts, or lots can develop on the same area of skin. Some types of warts are more likely to affect particular areas of your body. These are described below.

Common warts (verruca vulgaris)

Characteristics of common warts include:

  • round or oval in shape
  • they are firm and raised
  • they have a rough, irregular surface (cauliflower-like)
  • they are most common on the knuckles, fingers and knees
  • they range in size from smaller than 1mm to larger than 10mm
  • you may have one or several common warts

Verrucas (plantar warts)

Characteristics of verrucas include:

  • the skin area of the wart is white
  • they often have a black dot in the centre (blood vessel)
  • they are not raised from the surface of your skin
  • they appear on the soles of your feet
  • they can be painful because the weight of your body can force them to grow back into the skin

Plane warts

Characteristics of plane warts include:

  • they are a yellowish colour
  • they are smooth, round and flat-topped
  • they are usually between 2 and 4mm in diameter 
  • they usually occur in young children, mainly on the hands, face and legs
  • they can appear on the lower legs of females (due to the spread of HPV through leg shaving)
  • it is possible to have between one and several hundred plane warts, which can develop in clusters

Filiform warts (verruca filiformis)

Characteristics of filiform warts include:

  • they are long and slender
  • they more commonly develop on the neck, face and nostrils

Periungual warts

Characteristics of periungual warts include:

  • they have a rough surface
  • they are found under and around the fingernails and toenails
  • they can affect the shape of the nail
  • they can be painful

Mosaic warts

Characteristics of mosaic warts include:

  • they grow in clusters
  • the pattern that mosaic warts produce is ‘tile-like’
  • they are most common on the palms of the hands (palmar warts) and on the feet

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Risk factors

There are several risk factors that can potentially increase the likelihood of your wart turning malignant (cancerous) or requiring specialist care. 

Those most at risk are:

  • elderly patients
  • people with a weakened immune system, for example, organ transplant patients, those being treated for cancer and those with HIV and AIDS
  • people with an unusual number of lesions on the body 

Warts that are more likely to turn malignant include:  

  • warts that are growing rapidly
  • large warts that develop on their own (solitary lesions)
  • a wart that does not fit into a certain type or group of wart (atypical)

Causes of warts and verrucas 

Warts are caused by different strains of the human papilloma virus (HPV). The virus is present in the skin cells of a wart.

Over 100 different types (strains) of HPV have been identified. Different strains of HPV are responsible for causing different types of warts.

Spreading the virus

HPV is passed on through close skin-to-skin contact. It can also be passed on by indirect contact, for example, from contaminated objects, such as towels and shoes. Warts are thought to be contagious for as long as they are present on your body.

HPV is more likely to spread if the skin is wet, soft or has been in contact with a rough surface.

Warts can also be spread to other parts of your own body. For example, you can spread the virus if you:

  • scratch, knock or bite a wart
  • bite your nails or suck your fingers (if they have warts on them)
  • shave your face or legs

This can cause the wart to break up and bleed, making it easier for the virus to spread. People with scratches or cuts on the soles of their feet are particularly vulnerable.

Warts can also be spread through contact with contaminated surfaces. Examples of possible contaminated surfaces include:

  • the areas surrounding swimming pools
  • communal washing areas
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Your GP will be able to diagnose the type of wart that you have based on:

  • the appearance of your wart
  • where it is positioned on your body
  • the effect it has had on the surrounding skin

Due to their distinctive appearance, warts and verrucas are usually easy to identify through a visual examination of the affected area. Your GP will consider the following when they examine your wart:

  • the number of warts you have
  • where they are located on your body
  • the size of the wart
  • the shape of the wart
  • the colour of the wart
  • the texture of the wart’s surface

Your GP may gently cut away the surface of the wart to reveal a small black dot in the centre. If this is present, it will confirm that you have a verruca (plantar wart).

If you have a partner, your GP may ask you whether they also have warts, or whether any other members of your family have them.

Ruling out other conditions

By carrying out a thorough examination of your wart, your GP will also be able to consider any other possible causes and rule out any underlying conditions. Some of these are outlined below.

  • Corns and calluses: areas of thick, dry skin that are often yellow in appearance and caused by excessive pressure or friction.
  • Skin tag: a skin-coloured, benign (non-cancerous) growth of skin that usually develops on the neck, armpit and torso (upper body). Skin tags are usually painless.
  • Molluscum contagiosum: a contagious skin infection that is caused by the molluscum contagiosum virus. It produces small, firm, raised spots on the skin.
  • Moles: small, dark marks on your skin that can be flat or raised, smooth or rough. They may sometimes look similar to a cluster of filiform warts.
  • Seborrhoeic keratosis: common, benign skin lesions that are usually brown or black in colour.
  • Solar keratosis: scaly, rough spots that appear on skin that has been damaged by the sun.
  • Squamous cell carcinoma: a common type of skin cancer that appears as crusted lumps that are tender and slow-growing. It is very rare for existing warts to develop into a type of cancer, but the possibility will need to be ruled out.

Referral to a specialist

If your GP is concerned about your wart after carrying out an examination, they may refer you to a skin specialist (dermatologist) who will be able to assess your wart and confirm a diagnosis. However, in most cases, referral to a dermatologist is not necessary.

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Most warts clear up without treatment. However, the time it takes for a wart to disappear will vary from person to person. For example, warts may last longer in older children and adults.

Without treatment, warts usually clear up within two years, although some can take longer to go. It is also possible for warts to clear up without treatment within a few weeks, although this is less common.

Several types of treatment that may help clear warts more quickly are available. However, some treatments can be painful, and there is no guarantee that the warts will not come back again. Treatment can sometimes cause side effects including:

  • irritated skin around the wart,
  • pain, and
  • blistering.

Treatment options for warts depend on their location and how many there are.

Salicylic acid

Many over-the-counter (OTC) treatments, such as creams, gels, paints and medicated plasters, are available from pharmacies. The active ingredient in most of these treatments is salicylic acid. In two thirds of cases of warts, research has shown that they clear up within 12 weeks of treatment with salicylic acid.

Salicylic acid and other wart treatments also destroy healthy skin, so it is important to protect your skin before applying the treatment. Use petroleum jelly or a corn plaster to cover your skin around the wart.

Soak the wart in water for about five minutes, and then follow the instructions on the packet to apply the medication. Some GPs recommend putting a plaster on the wart after you have applied the medication.

Rub the dead tissue off the wart once a week, using a pumice stone or emery board (do not share these with anyone else).

You may need to apply the treatment daily for up to 12 weeks, or longer. Stop the treatment if your skin becomes sore.

For warts on your face, avoid treatments containing salicylic acid and seek your GP’s advice about treatment.

If you have poor circulation (for example, if you have a condition such as diabetes or peripheral vascular disease) you should seek your GP’s advice before using over-the-counter treatments containing salicylic acid. This is because there is an increased risk of damage to your skin, nerves and tendons.

Treatment with duct tape

There is limited evidence to support the effectiveness of treatment with duct tape. Side effects are uncommon. However, using duct tape on the face is not recommended because it can irritate your skin.

Treatment involves covering the wart with a piece of duct tape (adhesive tape) for six days, before removing it. You then soak the wart in warm water for five minutes and gently rub the dead tissue off using an emery board or pumice stone (do not share these with anyone else).

You should leave the wart uncovered overnight and apply a fresh piece of tape the following day. Treatment should be continued for up to two months.


In cryotherapy very cold liquid, such as nitrogen, is sprayed onto the wart to freeze and destroy the cells. A sore blister develops, followed by a scab, which falls off 7-10 days later.

Treatment usually takes between five and 15 minutes and can be painful, so you might need a local anaesthetic beforehand.

Cryotherapy treatment is usually carried out at hospital skin clinics, or at your GP surgery. Large warts sometimes need to be frozen several times, a week or so apart, before they clear.

If you have a wart on your face, your GP may recommend cryotherapy treatment because the risk of irritation is lower than using salicylic acid or duct tape.

A very cold spray (dimethyl-ether/propane) is also available from pharmacies, which you can apply yourself. However, you should not use this spray on your face.


Warts are not normally treated with surgery because they often come back afterwards. Surgery also usually causes scarring.

If surgery to remove warts is recommended, it will usually be carried out under general or local anaesthetic. Warts can be cut out of the skin (which can be useful if you have a few, large warts), or the skin of the wart can be scraped off using a spoon-like instrument called a curette. The aim of surgical treatment is to remove all traces of the warts.

Other surgical options include:

  • laser treatment, where the wart is destroyed using a very precise laser beam,
  • electrocautery, where the wart is burnt off using an electric current, and
  • photodynamic therapy, where the wart cells absorb a chemical that destroys them when activated by light (usually from a laser).

Some of these treatments may not be available on the NHS.

Chemical treatments

Treatments containing chemicals such as formaldehyde, glutaraldehyde and podophyllin can be used to remove warts. These chemicals are poisonous to skin cells, and are dabbed onto the warts in order to kill the skin cells there. Chemical treatments are available on prescription.

Treating warts during pregnancy

If you are pregnant and you have warts, your GP may recommend treatment using salicylic acid, cryotherapy or duct tape. Salicylic acid can be used to treat warts during pregnancy as long as it is used on a small area for a limited period of time.

However, you may decide to wait until after the birth before considering treatment. Cryotherapy can be painful and may cause blistering, pain and possible infection.

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Following treatment for warts, common side effects include:

  • pain
  • blistering
  • irritation of the skin around the wart

Treatment for warts rarely causes scarring and infection.

It is sometimes very difficult to treat warts effectively in people with weak immune systems, such as those with an illness like HIV and AIDS or those receiving treatment for cancer. In some cases, clearing up the warts may not be possible, even with treatment.

Psychological effects

If you feel that your warts look unattractive, it may affect your confidence and self-esteem, particularly if they cover a large area of your body. Warts can sometimes affect a person psychologically and have an adverse impact on day-to-day life.


Warts are usually harmless in people whose immune systems are working properly, and it is rare for any malignant (cancerous) change to develop in a wart. However, people with a weakened immune system have a higher risk of a wart becoming malignant.

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The advice listed below can help to prevent a wart or a verruca developing.

  • Do not touch other people’s warts.
  • Do not share towels, flannels or other personal items with someone who has a wart.
  • Do not share shoes or socks with someone who has a verruca.
  • Avoid scratching or picking your wart or verruca as this will encourage HPV to spread to other parts of your body.
  • Take care when shaving because the virus can be spread easily if you cut yourself.
  • Keep your feet dry and change your socks every day to help prevent warts developing on your feet.

Communal activities

Cover your wart or verruca when you are taking part in communal activities. For example:

  • wear flip-flops or pool slippers in shared areas, such as showers and swimming pool changing rooms
  • cover your wart or verruca with a waterproof plaster or a special verruca sock (available at pharmacies) when you go swimming or when you are doing physical education at school
  • wear gloves when using shared equipment, such as gym equipment (if you have a wart on your hand)
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