Warts are benign growths caused by a viral infection that affects the skin. They are specifically caused by one of the many types of human papillomavirus (HPV), and can affect patients of all ages and genders. Warts are most commonly found on areas that are frequently bumped or hurt, such as the hands, knees or feet, but can be located anywhere on the body. Although they’re contagious, warts are generally harmless.
Wellness & Prevention
The best way to avoid getting warts is to avoid coming into contact with someone else’s warts. You should also limit contact with your own warts, as they spread very easily. Picking at your warts or using the same nail clipper or emery board on healthy areas of the skin as you used on warts can both cause warts to spread and multiply. They also develop more often on broken skin.
There are many varieties of wart, each caused by different types of HPV:
- Common Wart (verruca vulgaris): Common warts are typically rough and can vary in size and number. Because warts have blood vessels near their surface, they can bleed easily if injured or bumped. The “black dots” often seen at the surface are really small blood clots at the ends of these blood vessels.
- Flat Wart (verruca plana): These warts normally have a smooth, flat and shiny surface, and are smaller than the common wart. They often occur in crops on the face, hands, wrists and knees.
- Plantar Wart (verruca plantaris): Plantar warts often occur on pressure points on the soles of the feet. They can be painful and look like a bump on the bottom of the foot with a central core that is skin-colored or black.
- Filiform Wart: These warts grow in finger-like projections that appear pedunculated (they have a stalk). They are most commonly found on the face, such as near the eyes or mouth.
- Periungual Warts: Similar in look to the common wart, periungual warts grow in clusters around the nails. They can be hard to manage and are sometimes resistant to standard treatments.
- Genital Warts (condyloma acuminatum): Genital warts appear on or near the genitals or anus, and are considered a sexually transmitted infection. They are smooth or cauliflower-like papules that are skin-colored or brown. Like other warts, genital warts are contagious. They can vary in size and number and occur in both men and women.
Warts should not be confused with molluscum, although the two skin conditions can look similar. Getting a correct diagnosis from a dermatologist will help make sure you get the best treatment.
Many warts don’t need treatment and disappear on their own. However, this can take months or even years. In the meantime, they may grow or spread significantly. Fortunately, there are many options available to manage warts. Some types of wart can need more than one treatment type or multiple treatment sessions.
Because warts are so common, there are many over-the-counter treatments that exist. These can be more effective if used after soaking the wart(s) in warm water for 5 to 10 minutes. Scraping off the top of the wart with a nail file or pumice stone can also help. If you use anything to scrape the wart’s surface, you should throw it away or only use it on the wart to avoid spreading.
- Topical salicylic acid, particularly 40 percent or higher, has been shown in clinical trials to be as effective as in-office treatments. However, treatment may take longer. There are several strengths available over-the-counter.
- At-home freezing treatments can be found in regular drugstores as well. Because these treatments do not get as cold as the freezing treatments performed by your dermatologist, they may not work as well.
- Applying duct tape over warts overnight (and every night until the wart disappears) can be a successful, easy and safe method of treatment. The evidence of this method working has been mixed.
- Zinc sulfate is a supplement that, when taken orally at 5 to 10 mg/kg daily, has been shown in several clinical trials to reduce or eliminate warts.
Some treatments may be prescribed by your dermatologist, and then are applied at home:
- Imiquimod is a topical cream that is applied to warts to aid the immune system in fighting the lesions. It is only available by prescription and is applied at home by the patient.
- 5-Fluorouracil is a topical chemotherapeutic agent used to treat pre-cancers in the skin, but it can also be used to treat warts when applied to the lesions and covered overnight. It is only available by prescription and is applied at home by the patient.
Several in-office treatments are also available from your dermatologist. These are performed during an office visit:
- Cryotherapy is a standard in-office treatment that uses liquid nitrogen to help destroy the wart as well as create an immune response to help clear the wart. In some people, this may cause mild to moderate discomfort both during and after the procedure. Patients may sometimes experience blistering following treatment. Cryotherapy can also cause a light spot in the area that is treated, although the same is true for many other wart treatments.
- Cantharidin is a chemical that comes from blister beetles. When applied to the affected skin, it causes blistering that makes the wart disappear afterward. This treatment is painless, but might take more than one application.
- Bleomycin is actually a cancer treatment that can also be used to treat warts. During an office visit, bleomycin is injected directly into the warts by your dermatologist. Although success rates are high, the treatment can be painful, so it’s often used only on recurrent or very resistant warts.
- Candida antigen is also injected directly into warts and has a good success rate. Depending on the location of the wart, injection can be painful. Sometimes, this treatment is combined with cryotherapy.
Less commonly, warts can be treated with surgery or laser treatments. This is normally only done for warts that have failed to respond to any other treatments. Sometimes, surgery or lasers may be used to treat warts that are growing quickly, that are causing a lot of discomfort or that keep coming back.
Recovery after wart treatment varies from person to person, and depends on the type of treatment used. It can take weeks or months before warts disappear, even after treatments. Often, more than one application of treatment is needed for the best results.
Many of the treatments listed above run the risk of causing temporary or permanent skin discoloration or even scarring. Other side effects include skin irritation or damage to nearby nails. Even if warts are gone, the person may still be contagious, especially with genital warts. Warts have a tendency to come back, so working closely with your dermatologist for the best treatment is important.