WHAT ARE PLANTAR WARTS?
Plantar warts (aka plantar verrucas) are superficial skin lesions caused by the human papilloma
virus (HPV). On the feet, they often look like a callus or corn and are found along the toes and
bottoms of the feet. Depending on their size and location, they may, or may not be painful. If the
wart is not tender, treatment is not always necessary, and the wart could resolve on its own over
the course of several months. If painful, several treatment options are available.
Warts live on the outer layer of skin, making them difficult to treat. The body has a difficult time
recognizing the virus, so treatment is often aimed at treatments that cause direct trauma to the
wart. Check out the list below for more information on at-home & over-the-counter remedies,
prescription topical medications, and in clinic procedures.
At-Home & Over-The-Counter Remedies:
Occlusion with duct tape or other non-porous tape
The purpose of using an occlusive tape is to try and smother the wart so it cannot survive. When used alone, it can be left on for days at a time but should be removed at least weekly. Between applications, the area should be cleaned, scrubbed with a pumice stone or similar device, and dried.
The area should be filed down with an emory board first. Then the acid is applied and covered with non-porous tape. The area should be washed with soap and water between treatments to avoid accumulation of residual acid. If OTC strength acids are not working, prescription strength medications can be prescribed by a physician (2). Salicylic acid should be avoided in persons with peripheral neuropathy (loss of sensation), unless otherwise instructed by a physician.
Adapalene gel (Differin)
Adapalene gel, most commonly used for acne, can also be used for the treatment of plantar warts. Once available by prescription-only, Adapalene is now available over-the-counter. Because it is considered off-label for plantar warts, it is recommended that you get permission from a doctor before trying. It is a good option for multiple warts, though, as it is simply a gel application and does not cause pain. The downfall of Adapalene is that it can take several weeks to months to see results.
2015 Study – 50 patients with 424 plantar warts were split into two groups: an Adapalene group (25 patients) and a cryotherapy group (25 patients). The adapalene group received twice daily treatments of topical 0.1% Adapalene gel under occlusion. After losing a patient in each group to follow-up, 48 patients’ results were reviewed. In the Adapalene group, all warts were cleared in under 56 days, while in the cryotherapy group, all warts were cleared in under 83 days with 1-4 treatment sessions (3).
Prescription Treatment Options:
5-fluorouracil (5-FU) cream (Efudex)
5-FU cream, used for actinic keratosis, can also be used as an off-label treatment for plantar warts. It works by inhibiting the viral replication at the cellular level by inhibiting DNA & RNA synthesis (5).
In-Office & Surgical Treatment Options:
Cantharidin / Canthrone (“aka Beetle Juice”)
Cantharidin, sometimes referred to as “Beetle Juice”, and often purchased as the product Catharone, is
a beetle vesicant that, when applied topically, acts as a blistering agent, separating the viral epidermal
skin tissue layer from the underlying, unaffected tissue layers.
The Procedure (What to Expect) – A liquid solution is applied after debridement of the wart. The area is
then covered with non-porous tape, which is kept on for a certain period of time. A blister usually forms
within 24 hours and days later, the blister will dry up and start to fall off. Follow-up appointments are
typically done 2-3 weeks later, at which time the area is debrided again, removing any non-viable
tissue. If there is residual wart, another treatment can be done at that time.
Check out my blog "Treating Plantar Warts with Beetle Juice" to learn more about Cantharidin
and how it is used to treat plantar warts.
As mentioned above, warts are superficial skin viruses that the body has a difficult time recognizing, which makes them difficult to treat. Therefore, the purpose of injecting the wart is to cause an immune response that will allow the body to recognize and get rid of the virus (1).
What is the wart injected with?
The wart can easily be frozen in the clinic using liquid nitrogen. Repeat treatments can be performed weeks apart. Cryotherapy is a common treatment choice for young children as it is safer than some of the other treatment options.
There are various types of lasers that can be used to destroy the wart virus. Multiple treatment sessions may be necessary, but laser can also be done in conjunction with other treatments.
If other conservative treatment options fail, needling of the wart can be considered. By
needling the wart, virus particles can be pushed into the body, which causes an immune
response (2,4). The procedure involves numbing up the area first, followed by several
punctures of the wart with a needle (4). Dressings are applied and left on for 24 hours.
Aftercare instructions should be dispensed, and follow-up appointments are made to
ensure clearance of the wart.
Check out my blog "How to Get Rid of Plantar Warts Without the Use of Chemicals" to
learn more about the Falknor's Needling Method for plantar warts.
Surgical excision of the wart can be done right in the office. After the area around the wart is
numbed with a local anesthetic, the wart is removed. Because the wart lives within the skin
layers, removal does not need to create an open wound; however, dressings are applied afterwards for protection and in the case of any bleeding. Scarring can occur if the dermal layer of the skin is traumatized with removal. Surgical excision should not be the first treatment option attempted but should have the greatest success rate since the wart is physically being removed.
HOW LONG DO WARTS LAST?
It is difficult to know how long any given wart will live. Some warts can resolve on their own, without treatment, after several months; however, with treatment, the wart may go away sooner. You and your doctor can discuss the details of the above treatment options, but many of them may require multiple treatment sessions spaced weeks apart from one another.
PREVENTING PLANTAR WARTS
Avoid touching the wart – Warts are often called “kissing lesions”, meaning that a wart on one side of the toe can spread to the adjacent toe just from rubbing against it. Therefore, you should prevent things from coming in contact with the wart. Also, avoid walking barefoot and use shoes/sandals while in public places. Lastly, avoid share personal items (e.g. towels) with others.
1. Cole, G.W. Plantar Warts. emedicinehealth. Retrieved from http://www.emedicinehealth.com/plantar_warts/page5_em.htm#what_are_treatments_for_plantar_warts
2. Fishco, W. (2010, December). Current Concepts In Managing Plantar Warts. 23(12). Retrieved from http://www.podiatrytoday.com/current-concepts-managing-plantar-warts
3. Gupta, R., & Gupta, S. (2015). Topical adapalene in the treatment of plantar warts; randomized comparative open trial in comparison with cryo-therapy. Indian journal of dermatology, 60(1), 102.
4. Needling – an effective treatment for warts and verrucas. Retrieved from http://www.betternowhealthcare.co.uk/news/26-needling-an-effective-treatment-for-warts-and-verrucas
5. Salk, R., Grogan, K., Chang, T., D’Costa, W. (2004, May). Exploring Alternative Treatment For Resistant Warts. 17(5). Retrieved from http://www.podiatrytoday.com/article/2598
Picture taken from Longhurst, B., & Bristow, I. (2013). The Treatment of Verrucae Pedis Using Falknor’s Needling Method: A Review of 46 Cases. Journal of Clinical Medicine, 2(2), 13–21. http://doi.org/10.3390/jcm2020013.
Disclaimer: The above information is meant for educational purposes only and should not be construed as medical advice. Should you feel that you are suffering from Plantar warts or another foot-related issue, please schedule an appointment to see the doctor.