A wart is a non-cancerous skin growth that occurs when a virus called human papillomavirus (HPV) infects the surface layer of the skin. In most cases, warts have a roughened surface and a clearly defined boundary. They most commonly occur on the fingers, hands, and arms, but can occur almost anywhere. Warts on the bottom of the feet are called plantar warts, and those that occur in the genital area are called genital warts.

Warts are usually painless. However, when they occur in an area that causes them to be subjected to pressure or rubbing, such as the bottom of the foot (plantar warts), they can become extremely tender. Genital warts that occur on the cervix are associated with a significantly increased risk of cervical dysplasia.

Conventional treatment for warts primarily involves a variety of methods to directly remove them. Over-the-counter topical treatments containing salicylic acid gradually dissolve the wart, but may take many weeks to work. (Note: Do not use this method on genital warts.) Podophyllin, trichloroacetic acid (TCA), and cantharidin are other substances that may be applied to a wart to remove it and which may be more effective, but they are generally only applied by a physician in an office setting. Other methods of wart-removal include freezing the wart with liquid nitrogen (cryotherapy), burning the wart, removing it with a laser, or cutting it out.

A completely different approach involves stimulating the immune system to destroy the wart. The drug Aldara (imiquimod) is the most common approach of this type, although injections of the immune-stimulating substance interferon are sometimes tried as well.

Warts often disappear on their own, as if the body has gotten “fed up” and decided to mount an immune response to remove them. Some evidence indicates that the body can be encouraged to do so through the use of the power of suggestion.

Hypnotherapy may be regarded as the deliberate use of the power of suggestion for therapeutic benefit. In three controlled studies enrolling a total of 180 people with warts, use of hypnosis caused warts to regress to a significantly greater extent than no treatment, placebo treatment, or (in one of the studies) salicyclic acid treatment.1,2Another study found that fake treatment with an x-ray machine can cause children’s warts to disappear.3 For more information, see the full hypnosis article.