What are warts?

Warts are commonly small, painless lumps that grow on the skin. However they can vary in size, shape and even occur in clusters. Warts most commonly affect the hands, fingers, knees and face, but can appear anywhere on the body.

Causes

Warts are caused by infection with the human papillomavirus (HPV). There are many different types of HPV that can cause warts. Warts can spread to other parts of the body, or to other people through direct contact. Warts may spread more easily if there is contact between injured or damaged skin, or if a wart has been scratched. It can take up to 12 months for a wart to first appear after infection with a HPV.

Types

There are many different types of warts, which are caused by different strains of the HPV and also the way that the body's immune system reacts to the virus. The most common type of warts include:

Common warts

Common warts are usually painless. They can grow anywhere on the body, but most commonly occur on the hands and fingers, elbows and knees.

Plantar warts

Plantar warts, which are sometimes called verrucas, most commonly occur on the sole of the foot. This type of wart can become painful when weight is put on the foot, such as during walking or running.

Common wart on a hand.A common wart typically grows on the hands, fingers and knees. 

Plantar wart on the sole of a foot.A plantar wart most commonly grows on the sole of the foot. 

Genital warts

Genital warts are a very common sexually-transmitted infection (STI) that can be spread through intimate physical contact. These warts grow near the genitals and are not always easily visible as they can be flat. Sometimes multiple warts can cluster together to form a cauliflower-like shape.

Sexually-transmitted infection

A viral or bacterial infection contracted through sexual intercourse or genital contact. Such an infection can lead to development of diseases such as chlamydia, gonorrhea, genital herpes and AIDS.

Signs and symptoms

Warts are colored white, pink or skin color and can be rough to the touch. Also, warts may look like they contain small black dots, which are clotted blood vessels.

Methods for diagnosis

Warts can usually be identified just by looking at them.

Types of treatment

Many warts will disappear on their own within a couple of years. However, there are several different methods available that can be used to remove warts. The type of treatment used to remove warts depends on how many warts you have and where they are located. Unfortunately, removing the warts does not get rid of the virus and sometimes the warts can reappear.

Medication

Your doctor may prescribe a medicated solution or cream containing salicylic or lactic acid to apply to the wart. These creams are applied directly to the wart, one or more times each week until they are gone.

Creams containing salicylic or lactic acid can be used to remove a wart. 

Cryotherapy

Cryotherapy is a procedure that uses liquid nitrogen to destroy warts by freezing them. This is usually performed by a doctor in their office.

Laser treatment

Laser therapy uses an intense light to destroy warts. This procedure is usually performed under an anesthetic to prevent pain.

Prognosis

Warts are not usually very serious. Many warts clear up by themselves within a couple of years.

Prevention

There is no exact way to prevent getting the viruses that cause warts. You may be able to reduce the chances of warts spreading to other parts of your body, or to other people, by not picking or scratching warts.

FAQ Frequently asked questions