Am Fam Physician. 2011;84(3):296
See related article on nongenital cutaneous warts.
What are warts?
Warts are bumps on the skin that can happen anywhere on the body, but usually on the hands or feet. They are caused by infection with the human papillomavirus, or HPV. Warts typically do not cause pain or bleeding.
There are several types of warts. Common warts are usually found on hands and around the nails. Warts on the bottom of the feet are called plantar warts.
Are warts contagious?
Warts can spread to different parts of your body if you touch or scratch them. You can also spread HPV to other people if you share towels or razors. You can get common warts by biting your nails or plantar warts from walking barefoot in public areas, like a locker room.
Do they need to be treated?
Not always. Most warts will go away on their own, but it may take up to two years. Some warts will never go away without treatment.
How are they treated?
Warts can be treated with an over-the-counter medicine called salicylic acid. This treatment works best if you first soak the wart in warm water and file down the thick skin with a pumice stone or emery board. Putting duct tape over the medicine may help, but this hasn't been proven. Warts can come back after treatment.
You should tell your doctor if you're not sure a bump on your skin is a wart or if the wart is swollen, red, oozing, or bleeding. Your doctor can tell you about other treatments if over-the-counter treatments don't work. Your doctor can freeze the wart with cryotherapy, although it may take several treatments for it to work. Cryotherapy kits that you can use yourself are also available over the counter.
There are other treatments for warts, but it's unclear whether they are effective. Warts can be hard to get rid of, especially plantar warts.
Where can I get more information about warts?
AAFP's Patient Education Resource
American Academy of Dermatology