What can I do about plantar warts on my feet?

DEAR DOCTOR K:

I have warts on the bottoms of my feet. How can I get rid of them?

DEAR READER:

The warts on the soles of your feet are called plantar warts. They are essentially the same as other warts except that they are hard and flat. I’ve had them, and boy, are they aggravating.

Warts are highly contagious, so they’re easy to pick up, especially if you walk barefoot on moist, warm or dirty surfaces. They result from infection with the human papillomavirus (HPV). (It’s a different strain than the one that is sexually transmitted and causes cancer of the cervix.)

If you have a plantar wart and also have diabetes or another medical condition that makes you prone to infections or slow to heal, see your doctor. A plantar wart can get infected. In people with diabetes, foot infections do not heal easily. If they don’t heal, an amputation of the foot may be necessary.

A plantar wart sometimes can cause pain when you walk. That intermittently happens with mine. Pain is another reason to consider treatment. However, keep in mind that warts of all types can come and go. Be patient, since the wart may go away on its own — and that’s what has happened in my case.

If you are not having symptoms and are not diabetic, it is reasonable to do nothing. One reason to seek treatment, even if a wart is not causing symptoms, is that it may grow or seed other warts across your foot. In my experience (professional and personal) that does not happen often.

If you want to try treatment, you have several options. You can try an over-the-counter preparation that includes 40 percent salicylic acid (Clear Away, Compound W and others). You can also consult a foot-care specialist, who may apply a stronger topical preparation.

Yet another option is topical fluorouracil (Carac, Efudex, Fluoroplex). This prescription cream’s effectiveness isn’t certain, but if you prefer medication to surgery, ask your doctor about it.

There are several quicker but more painful options. They usually are performed by dermatologists and skin surgeons, not by primary care doctors.

The first is to freeze away the wart (cryotherapy). The frozen tissue dies and falls off, like a scab. The wart also can be cut out with a scalpel under local anesthetic.

Finally, there are two types of laser treatment. The first is a carbon dioxide laser to remove the wart, again with a local anesthetic. A less painful option is pulse-dye laser removal. The laser destroys red blood cells in the wart. This deprives the wart of oxygen and nutrients without harming surrounding skin and tissue. (This technique is not available everywhere.)

We have more information on plantar warts in our Special Health Report, “Foot Care Basics.” You can learn more about it here.