Warts

What are warts?

Warts are small rough lumps on the skin caused by a viral infection known as the human papilloma virus. Most people develop one or more warts at some time in their lives, usually before the age of 20. Warts most commonly affect the hands and feet (verrucas), but can affect any part of the body. Sometimes only one or two warts develop. Sometimes several occur in the same area of skin. Warts are harmless; they usually disappear without treatment, although this can take a few months to several years.

What causes warts?

Warts are caused by infection in the outer layer of the skin (epidermis) with a virus called the human papilloma virus (HPV). The virus tends to enter the skin through tiny breaks in the skin surface. A common example is verrucas, which can be caught from the floors of shower cubicles and the areas around swimming pools. HPV is not highly contagious (i.e. not easily passed from one person to another), it is not clear why some people develop warts while others do not. People with a weakened immune system (immunosuppressed) have a higher risk of developing larger numbers of warts, which can be very persistent and hard to treat.

What do warts look and feel like?

Warts on the feet can be painful. The shape and size of warts vary and they are sometimes classed by how they look. This leaflet does NOT discuss anogenital warts, which affect the skin around the anus and/or genital skin.

Common warts on the feet (plantar warts / verrucas) and hands - these vary in size from just a few millimetres to more than one centimetre. They may have a rough surface that protrudes (is raised up) from the skin surface. Close inspection with a magnifying glass may reveal small black dots.

Mosaic warts - this is when several warts join together on the bottom of the feet.

Filiform warts - these are often solitary (one lesion) and are most commonly found on the face and neck, but can occur on any part of the body. They are often skin-coloured with finger-like projections.

Plane warts - the face and backs of hands are the most common sites. Lesions are often numerous, appearing as small (less than 5 mm), round, and slightly elevated lesions with a smooth surface.

Things that you can do to help yourself and other people

To reduce the chance of passing on warts to others:

• Do not share towels 
• When swimming, cover any wart with a waterproof plaster - swimming is a vital life-saving skill and children should attend swimming as usual. Some people with verrucas prefer to wear a waterproof sock which you can buy from pharmacies, however, it is worth noting that this has not been proved to make a difference to transmission and makes it very obvious that you have a wart, which may cause embarrassment
• If you have verrucas, 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:

• Do not scratch warts or pick them
• Do not bite nails or suck fingers that have warts 
• If you have a verruca, change your socks or tights daily

Things you can do to treat warts

There is no need to treat warts if they are not causing you any problems. Half the number of children with warts will find they have disappeared within a year without any treatment. Two-thirds will have gone within two years. Sometimes warts last longer, particularly in adults or if you have a weakened immune system (immunosuppressed), in which cases warts may persist for many years.

If warts on the hands and/or feet are painful; the pain can be relieved by paring the warts - the affected skin should be soaked in warm water and the thickened skin filed away with a pumice stone or emery board. Care should be taken not to scrape the surrounding normal skin, and not then use such items on healthy skin, so as to avoid spreading the virus.

If warts on the hands and feet continue to cause difficulties there are a number of treatments that can be tried. People more likely to improve with treatment are younger people with common warts. People less likely to respond to treatment are those with mosaic warts older people, and those with a weakened immune system (immunosuppressed). Common warts can be managed as follows:

• Paints, gels and plasters containing salicylic acid are available from pharmacists (see further down in this leaflet for advice on how to use salicylic acid)

• Duct tape (available online or from DIY shops) - while there is not a lot of evidence to support the use of duct tape on its own, it might still be well worth trying, especially in children. The wart/s should be covered with duct tape for six days; if the tape falls off it should be replaced with a fresh piece. The tape should then be removed and the affected area soaked in luke-warm water and the wart pared down to remove any dead skin cells. The wart should then be left uncovered overnight and the duct tape reapplied once again in the morning. This process can be continued for up to two months. Duct tape might be more effective if a salicylic acid paint or gel is first applied to the wart before then covering in duct tape

• A cold ‘freeze’ spray may be purchased from some pharmacies; it cannot be prescribed by your doctor. This treatment may cause discomfort and is not suitable for very young children or those with poor circulation. It is important to follow the instructions that come with the spray

• Follow this link for information on specific treatment of different types of warts

Treating warts with salicylic acid

Salicylic acid treatment can be purchased from a pharmacy and usually comes as a paint or a gel. Read the instructions in the packet on how to use it, or ask your pharmacist for advice. If you have diabetes or poor circulation, you should only use salicylic acid on the advice of a doctor. Treatment is usually as follows:

• Before applying the paint or gel, the feet should be soaked in warm water and the thickened skin filed away with a pumice stone or emery board. Care should be taken not to scrape the surrounding normal skin, or using these items on healthy skin so as to avoid spreading the virus

• You need to apply the salicylic acid each day for up to three months. Perseverance is important; if treatment is not continued it is unlikely to work. The paint /gel should be applied carefully to the wart and not the surrounding normal skin. If the wart becomes too sore treatment should be stopped for a few days, and then started again. Applying Vaseline to protect the skin surrounding a wart before applying the salicylic acid may reduce the likelihood of the skin becoming sore

• You MUST NOT apply salicylic acid to the face because of the risk of skin irritation which may cause scarring, or damage to eyesight if it is gets in eyes

• Acid lotions and paints are flammable - keep them away from open fires and flames

Make an appointment at your GP surgery

If warts have not improved with the treatments mentioned above and are causing significant problems, some GP surgeries may be able to offer treatment with a much colder freeze spray called liquid nitrogen (cryosurgery). Not all GP surgeries have access to this so before you make an appointment phone your GP surgery to see if this is available. Liquid nitrogen can be used on common warts and some filiform warts. It is NOT suitable for young children as it is painful, can cause a blister, and several treatments given every 1-3 weeks are usually needed. Even then there is no guarantee that the treatment will work. Cryosurgery can also leave a scar and/or area of discolouration, and damage the nail permanently if used on the skin surrounding a nail.

Referral to a specialist

There are several other treatments that can be used by specialists. Treatment is not usually available on the NHS to treat warts unless there are complications or they are very severe. Treatment is available as a private (paid for) service from many podiatrists, and some dermatologists. There is no guarantee that other treatments will help, even with surgical treatment (where the wart is cut out or scraped out) there is a significant chance that the wart will regrow.

Helping with other skin conditions

If you, a family member, or friend have an undiagnosed skin condition; or you want to learn more about how to treat skin conditions, please view our short video on how to get the best from this website.