Warts are raised bumps on your skin caused by the human papillomavirus (HPV). Warts have plagued humans for thousands of years — they have been discovered on 3,000-year-old mummies and were mentioned by Shakespeare. Although warts generally aren’t dangerous, they are ugly, potentially embarrassing, and contagious. They can also be painful.

There are more than 100 types of HPV, the virus that causes warts. Almost all types of HPV cause relatively harmless warts that appear on your hands or feet. However, there are a few strains of HPV that cause warts on, in, and around your genitals. In women, these warts — called “genital warts” — can eventually lead to cervical cancer, a potentially fatal disease.If you think you have genital warts or think you have been exposed to them, you should see a doctor right away.

There are five major types of warts. Each type appears on a different part of the body and has a distinct appearance.

Common warts

Common wartsusually grow on your fingers and toes, but can appear elsewhere. They have a rough, grainy appearance and a rounded top. Common warts are grayer than the surrounding skin.

Plantar warts

Plantar warts grow on the soles of the feet. Unlike other warts, plantar warts grow into your skin, not out of it. You can tell if you have a plantar wart if you notice what appears to be a small hole in the bottom of your foot that is surrounded by hardened skin. Plantar warts can make walking uncomfortable.

Flat warts

Flat warts usually grow on the face, thighs, or arms. They are small and not immediately noticeable. Flat warts have a flat top, as if they’ve been scraped. They can be pink, brownish, or slightly yellow.

Filiform warts

Filiform warts grow around your mouth or nose and sometimes on your neck or under your chin. They are small and shaped like a tiny flap or tag of skin. Filiform warts are the same color as your skin.

Periungual warts

Periungual warts grow under and around the toenails and fingernails. They can be painful and affect nail growth.

You should see your doctor if:

  • you have warts on your face or another sensitive part of your body (e.g., genitals, mouth, nostrils)
  • you notice bleeding or signs of infection, such as pus or scabbing, around a wart
  • the wart is painful
  • the color of the wart changes
  • you have warts and diabetes or an immune deficiency, such as HIV/AIDS

Although warts usually go away on their own, they are ugly and uncomfortable, so you may want to try treating them at home. Many warts respond well to treatments available at the drugstore.

Some things to remember:

  • You can spread warts to other parts of your body, and they are contagious to others. If a treatment requires that you rub the wart with a fingernail file or a pumice stone, don’t use that utensil on any other part of your body, and don’t allow anyone else to use it.
  • Don’t try to treat warts on your feet if you have diabetes. See your doctor. Diabetes can cause loss of sensation in your feet, so you can easily injure yourself without realizing it.
  • Don’t try to remove warts on your face or another sensitive part of your body (such as your genitals, mouth, or nostrils) with at-home treatments.

Freezing treatments

These over-the-counter treatments spray concentrated cold air (a mixture of dimethyl ether and propane) onto your wart. This kills the skin and allows you to scrape away the surface of the wart. These treatments are a good choice if you want to try to remove a wart quickly, but they aren’t strong enough to remove all warts.

Treatments and patches containing salicylic acid

You must use these products every day, often for a few weeks. They’ll work best if you soak the wart in water for about 15 minutes before you apply the treatment.

Shop for salicylic acid treatments.

Duct tape

Some people have had success treating warts with duct tape. The process involves covering the wart with a small piece of duct tape for several days, then soaking the wart, and, finally, rubbing the wart to remove the dead skin. This approach can take several rounds of treatments to work.

If your wart doesn’t respond well to at-home treatments, your doctor may be able to help. Remember, always see your doctor if you have diabetes and have warts on your feet.

Liquid nitrogen

Your doctor may freeze your wart with liquid nitrogen. This can be a bit painful, but usually works well. More than one treatment may be required. Freezing causes a blister to form under and around your wart. This lifts the wart away from the skin within about a week.

Surgery

Surgery is usually only considered if a wart hasn’t responded to other treatments. Your doctor can cut away your wart with a surgical knife or burn it with electricity. You’ll need to receive a shot of anesthetic first, and these shots can be painful. Surgery may also cause scarring.

There are ways to prevent warts and keep them from spreading to other parts of your body if you already have one. Follow these simple guidelines:

  • Wash your hands regularly, especially if you’ve been in contact with someone with warts.
  • Don’t pick at your warts.
  • Cover warts with a bandage.
  • Keep your hands and feet dry.
  • Wear shower shoes (flip-flops) when in a locker room or communal bathing facility.