A plantar wart is a growth of skin on the bottom of the foot caused by a virus. The most common areas of growth are in pressure places, such as the heels or balls of the feet. The virus is not highly infectious, but you can pick it up in warm moist areas where you walk barefoot, such as showers, locker rooms, or public swimming areas. If you already have a wart, you can also spread the virus on your own feet. Warts will often go away on their own. However, some warts can spread easily or may be in a very tender spot. Salicylic acid, duct tape, and freezing the warts are common and sometimes effective remedies. People with warts that are painful enough to interfere with everyday function or that are spreading rapidly may need more intensive treatment from their doctor. The process may involve surgical excision or another procedure that can leave damage and require a longer healing process.
Researchers from China examined the benefit of applying an infrared heating device to the warts. The study, published in the Journal of Infectious Diseases, showed promising results in decreasing pain and eliminating the wart.
The randomized trial involved 60 patients with plantar warts. The patients were all scheduled for 5 days of 30 minutes of heat treatment (hyperthermia). The participants were randomly assigned to the actual heating device that produced heat in the area or to a sham treatment that produced a red dot on the area but no heat. After 3 months, patients reported:
The results are promising, because it was not only effective in treatment but did not leave the damage common with other treatments. There are some problems with this study. Patients that received the sham treatment would not have felt heat and therefore may have guessed that they were receiving sham treatment. At the same time, the treatment group was able to feel the heat. This knowledge may have affected how pain improvements were rated by the patients.
If you have a plantar wart, it will most likely go away on its own. If the wart is spreading into a large area, if it interferes with activities like walking, or if it is not responding to home treatments, consult your doctor. From there, you and your doctor may discuss options that best suit your lifestyle. Some treatments require frequent applications, where others may be quicker but require longer recovery as the wounds heals. Perhaps local hyperthermia treatment will become more available if further research supports the findings of this study.
The American Academy of Dermatology
American Podiatric Medical Association
Huo W, Gao XH, Sun XP, et al. Local hyperthermia at 44 degrees C for the treatment of plantar warts: a randomized, patient-blinded, placebo-controlled trial.J Infect Dis. 2010 Apr 15;201(8):1169-72.
Last reviewed August 2010 by Brian P. Randall, MD