Warts grow in the epidermis, the upper skin layer. A typical wart has a raised, rough surface. (Some, like those on the face, may be smooth and flat.) The center of a wart may be flecked with dark dots; these are capillaries that supply it with blood.A wart virus infection is different from a bacterial infection such as strep throat, which can be caught, treated, and eradicated because it progresses in a distinct, reliable pattern. The ways of warts are much less predictable. According to dermatologist Dr. Suzanne Olbricht, “The wart virus resides in the upper layer of the skin, and who knows where or when you picked it up? The virus could have been there for years. Then it makes a wart for reasons we don’t understand. And when the wart goes away, you can still find the virus in the epidermis.”
Studies indicate that about half of warts go away on their own within a year, and two-thirds within two years, so “watchful waiting” is definitely an option for new warts. But some experts recommend immediate treatment to reduce the amount of virus shed into nearby tissue and possibly lower the risk of recurrence. If you prefer not to wait it out, you have several treatment options:
- Salicylic acid. This is the main ingredient in aspirin, and it should usually be your first choice. According to one study, salicylic acid is the only topical treatment (treatment applied directly to the skin) that clearly outperforms a placebo. (The study, in the August 2011 issue of the British Journal of Dermatology, combined and reanalyzed data from a number of previous studies.) Salicylic acid costs little, has minimal side effects, and comes in various over-the-counter preparations, including liquids, gels, and patches. Concentrations range from 17% to 40% (stronger concentrations should be used only for warts on thicker skin). To treat a wart, soak it for 10 to 15 minutes (you can do this in the shower or bath), file away the dead warty skin with an emery board or pumice stone, and apply the salicylic acid. Do this once or twice a day for 12 weeks. Warts in thick skin, like the bottom of the foot, may respond best to a patch that stays in place for several days. Continuing treatment for a week or two after the wart goes away may help prevent recurrence.