Warts

As summer is winding down, hopefully most people have managed to enjoy the nicer weather by spending their time outdoors.  Going barefoot, wearing flip-flops, and swimming in pools exposes our feet to the outdoor environment. Warts are common, benign soft tissue infections that can be picked up from communal places. They are caused by infection from viruses in the human papilloma (HPV) family, which can invade your skin through small cuts or breaks.  Warts present as small, hard, raised, callus-like soft tissue lesions, which when located on the bottom of the foot, can be quite painful. There can be small brown or black spots present within the lesion, which are often mistaken for corns or calluses. Most warts are self-limited, meaning, that eventually the body recognizes the wart and eliminates it. However, it can take multiple years for this to happen, and warts on the bottom of the foot are known to be recalcitrant and can spread to other parts of the foot, or even to the hands and/or body.

The main way to prevent warts is to avoid contact with the HPV virus. Avoid walking barefoot on moist surfaces and wear shower shoes when walking in areas that have excess water (around pools, public showers, or locker rooms).  If your feet are overly sweety, try to keep them dry with the use of powders or changing socks frequently. There are also topical antiperspirants that can be applied to the foot for people with excessive sweating (a skin condition known as hyperhidrosis). It is much easier for the HPV virus to invade your skin if the skin is moist and the pores are open. Do not share towels, socks or shoes with other people as well. Also, protect your skin.  Make sure that your skin is intact and free of cuts, scrapes, or ruptures.  Treat these issues immediately so that they resolve in a timely fashion.  Additionally, warts are easier eradicated the sooner they are recognized and treatment is started.

There are many ways to treat warts, depending on their size and location. Over-the-counter treatment typically consists of applying salicylic acid once or twice a day over the course of 6-8 weeks.  The higher the concentration of salicylic acid, the stronger the treatment. Most over the counter salicylic acid formulations do not contain a high enough concentration to remove the plantar wart, despite what the packaging advertisement insinuates. Freezing is usually ineffective for warts on the bottom of the foot due to the incomplete penetration of the cold therapy through the entire wart.  In fact, freezing can actually lead to the wart spreading to the surrounding skin.

In our office, most warts are effectively and painlessly treated with topical application of monochloroacetic acid and 60% salicylic acid (over-the-counter salicylic acid strength is limited to under 40%) underneath an occlusive bandage worn for 48 hours. Even large warts that have been present for some time can resolve within 1 or 2 treatments.  For chronic warts, we will also typically prescribe an antiviral cream to apply nightly in between office treatments.  A high percentage of warts can be eliminated without the need for need for surgical excision.