warts

There are several types of human warts. These include common warts (verruca vulgaris), flat warts, plantar warts, and filiform warts (the kind that grow on witches' noses). All warts are benign tumors of the top layer of the skin, caused by distinct viruses. The common wart is a product of the human papilloma virus (HPV), of which there are a multitude of strains, associated with different types of warts. We don't know why some people get warts and some don't. We assume it is due to variations in individual immune systems.

Common warts begin as small, smooth, fleshy-colored masses and evolve into dome-shaped, gray-brown, rough growths with black dots on the surface (old clotted blood vessels).
Filiform warts are fingerlike, flesh-colored projections most commonly observed about the mouth, eyes, and nose.
Flat warts (verruca plana) are slightly elevated, flat-topped, pink, light brown, or light yellow. Generally they are numerous, found around the forehead, mouth, and the backs of the hands.
Plantar warts are found on the soles of the feet. They are flat or slightly raised, and may have multiple visible dark specks within them. They are painful if they lie over a pressure point on the foot.

Common warts (verruca vulgaris) are most common in children and young adults, but can appear at any time in life. Most warts disappear spontaneously in a few months, but they may last from years to an entire lifetime. They spread by touch (autoinocculation) from site to site. The hands are the most commonly involved area, but warts may be found anywhere on the skin surface. Warts commonly appear at sites of trauma, on the hands, around the fingernails (from nail biting), and on the soles of the feet (plantar, not "planter's" warts).

Assuming waiting for the wart to go away on its own is not an attractive option, treatment of warts generally involves various strategies to get the top layer of the skin containing the wart to peel off. Warts have no "roots" penetrating into the dermis, or deep layer of the skin. Because warts are confined to the top layer of the skin (epidermis), they can be removed with little, if any, scarring. Methods of removal that scar are therefore best avoided, especially in children. Topical salicylic acid preparations, freezing with liquid nitrogen or CO₂ spray, or very light electrocautery are the preferred methods for initial therapy by dermatologists. Surgery is used for resistant or very large lesions, but of course is avoided if possible because of inevitable scarring.

Over-the-counter products for removing warts are basically salicylic acid (the chemical base of aspirin) in some sort of vehicle to deliver the acid to the wart. Products like Compound-W® or Transversal® are solutions with a vehicle that dries to a film. Mediplast® is a 3x4 inch sheet of sticky-on-one-side material that contains 40% salicylic acid. The normal moisture of the body draws the active chemical into the wart, the acid dissolves the bonds between the skin cells, and the wart tissue crumbles apart as a result.

Common warts on the fingers are comparatively easy to get rid of. Get some Mediplast® or similar salicylic acid plaster, and cut it to fit the wart. Tape it to the wart with duct tape (yes, duct tape - it sticks better). Every few days, change the plaster and grind the now soft, white wart tissue down with a coarse emery board you use for nothing else. If your child complains that the acid plaster hurts, make sure it covers only the wart and not normal skin, and perhaps let the wart dry out and harden for a day before restarting the treatment.

If plantar warts are painless, there is no need to treat them - out of sight, out of mind. However, plantar warts can be a great irritation because the pressure of walking tends to push them into the sole of the foot like a stone in the shoe. These warts obviously will have to have something done about them. Plantar warts can basically be attacked the same way as common warts; you will probably find something like the Dr. Scholl's® Clear Away Plantar system helpful. This consists of precut plasters and doughnut-ring sticky protective covering pads. Every few days, change the salicylic acid plaster and grind down the crumbly wart tissue with the emery board. It takes weeks and weeks but the treatment is cheap as dirt and does not hurt.

Recently, the use of common duct tape alone to cure warts has been found to be more or less ineffective¹ in treating warts. I used this treatment with some patients for a while when an earlier study found it useful. A more thoroughly controlled study gave less impressive results. That's the way it often goes.