To treat or not to treat?

The common warts, especially in children, sometimes go away spontaneously within a few days. In adults, healing is often much longer, but two-thirds of warts go away on their own before 2 years. Since these are benign lesions and treatments are sometimes damaging to the skin, it is not always justified to initiate treatment. There are different reasons for treating a common or plantar wart:discomfort that they create (physical or aesthetic), the pain, their multiplication, the risks of contagion or complications, etc.

Regardless of the treatment employed, this does not completely eliminate the virus. After the wart heals, the virus remains in the epidermis and can reactivate. It is the immune system that keeps it under control, but the recurrences can be frequent.

Treatments

Treatment will depend on theage of the patient, of the type the verrue and its emplacement. Most treatments require several sessions (especially for plantar wart, which is more resistant to treatment). Doctors tend not to treat plantar warts if they aren’t painful. There are many treatments out there, but none are completely guaranteed.

You may have to try several treatments before you get rid of the problem. Finally, let us mention that thePlacebo effect is quite powerful in the treatment of warts. Indeed, the application of placebo solutions shows cure rates varying from 0 to more than 70% (with an average of 27%).

Products based on salicylic acid. Several salicylic acid products (some also contain lactic acid) are available without a prescription and may work well, especially for common warts (e.g. Duoplant® in Canada, Duofilm® in Canada, Compound W ® and Off-Ezy® in Canada). The effect of salicylic acid is comparable to that of a burn: after application, the skin takes on a withered and whitish appearance. A thin layer of this withered skin is removed every day. The acid also creates local inflammation which could help the immune system fight off the virus.²⁵. It is important to strictly follow the manufacturer’s instructions and apply the product daily for it to be effective. These treatments are usually followed for 3 to 4 weeks.

The concentration of salicylic acid varies from one product to another, between 10 and 60%. The concentration chosen will depend on where the wart is located and its resistance to treatment. Some products are in the form of a liquid, others as a gel or as a bandage to put on the wart. It is not recommended to use them on the face or on other sensitive areas.

NB The faster applications are started, the lower the risk of the virus spreading.

Cryotherapy. Cryotherapy is a process that uses cold to “burn” the wart. The doctor files directly from theliquid nitrogen at -196 ° C on the wart, which causes the wart to detach. Nitrogen is applied until the skin is frozen for about 5 seconds. The product destroys both the wart and the virus, but then a blister appears, and the procedure is painful. Usually, several sessions (2 or 3 weeks apart) are necessary to make the wart disappear permanently. This treatment can be made less painful by applying a local anesthetic 1 hour before the procedure. Note also that this treatment can depigment the skin or on the contrary make it darker. A product (Freeze-Away® in Canada, Cryopharma® in France) based on cold, less intense than liquid nitrogen, is also available over the counter in pharmacies.

Many other treatments exist and can be offered for plantar warts and more resistant warts.

• La cantharidine in Canada (Canthacur®, Cantharone®). Sold without a prescription, this product must however be applied by a doctor or podiatrist. A blister forms under the wart and disappears within 1 to 2 weeks. The application is not painful and this product can be effective on plantar warts²⁵ ;
• After performing local anesthesia, the doctor may make an incision and extract the wart or destroy it by electrocoagulation. These two minor procedures must be performed with care to avoid scar formation;
• Again in rebellious cases or in people with fragile immunity, it is possible to inject interferons in the wart (in Canada). Interferons are substances that fight viral infections;
• In the most severe cases, an injection of bleomycin, a substance that prevents cells from multiplying. This process is suitable for all types of warts, but it is not very popular because of the intense pain it causes;
• Other products are sometimes used: imiquimod, trichloroacetic acid, cimetidine and 5-fluoro-uracil or 5-FU (often used for genital warts);
• Another method is to destroy the wart by laser. This technique does not cause any bleeding, but it can take a long time to heal and often leaves a scar. It is therefore a last resort solution.

In 2006, a meta-analysis² compiled the results of 60 clinical trials on the treatment of warts (excluding genital warts). According to its authors, the salicylic acid solutions are the treatment with the most evidence of effectiveness. Their use leads to healing in 73% of cases. As for the cold treatment withliquid nitrogen, its effectiveness would not be superior to that of salicylic acid, contrary to what has long been believed. However, a randomized trial published in 2010 compared the effectiveness of these two treatments in 250 patients. For common warts, cryotherapy seemed to be more effective. In contrast, cryotherapy, application of salicylic acid orabstention from treatment all gave equivalent results on plantar warts²⁶.