Plantar Warts: Information and Doctors

Plantar warts are often painful and typically develop on the heels or other areas of the sole of the foot. Externally, they appear flat or barely raised and are visible only as a round circle. They grow inward like a thorn and are often only clearly visible on the surface after the callus has been removed.

The interior of a plantar wart can reach twice the diameter of the circle visible from the outside. In rare cases, this type of wart can also appear on other parts of the body, such as the hands, through transmission.

A great many children and adolescents—as well as adults—are affected by this skin condition.

Plantar warts are not dangerous, but they are highly contagious. They can spread quickly to other parts of one’s own body and to other people through touch, leading to new plantar warts. Prompt treatment is therefore highly recommended.

Plantar warts are a type of viral wart. They are caused by an infection with human papillomaviruses (HPV), which are widespread and can also cause other types of warts.

These viruses thrive in warm, humid environments and can multiply easily there. That is why the risk of infection is high in

• swimming pools,
• locker rooms,
• saunas, or
• gyms

is particularly high. The viruses responsible are very resilient and can survive here for months without a host under favorable conditions. The risk increases further if you walk barefoot in these locations.

HP viruses can be transmitted through contact or smear infections. Direct skin contact is therefore not absolutely necessary for transmission. The viruses can be deposited on the floor by an infected person walking barefoot and, from there, be transferred to a new host when someone walks barefoot. A plantar wart often takes a long time to develop after exposure. 

People with cracked skin on the soles of their feet are at increased risk. The viruses can take hold more easily through these cracks.

These circumstances make swimming pools the riskiest places for infection. Chlorinated water dries out the skin, making it easier for HP viruses to penetrate the skin and enter the body.

There is a high risk of infection with HP viruses in swimming pools and saunas © yanlev | AdobeStock

People with weakened immune systems or poor circulation are particularly susceptible to plantar warts.

The development of plantar warts can vary greatly. Some grow deep and root-like inward, while others disappear just a few days after they appear.

However, plantar warts are very persistent and can recur repeatedly. The viruses can also spread to other parts of the body through contact with affected areas.

To the best of our current knowledge, plantar warts do not spread internally within the body.

Plantar warts are difficult to see beneath the surface layer of calloused skin. The time between infection and onset (also known as the incubation period) can last a few weeks or even several months. This naturally makes it nearly impossible to trace the source of the infection.

At first, only a small black dot appears on the affected area of the body, which usually goes unnoticed initially. In most cases, the wart then draws attention to itself through itching or pain at the site.

This pain is similar to thorns piercing the skin when walking due to the weight of the body. This is where the name of these unpleasant warts comes from. The pain is also often compared to stepping on a small, sharp stone.

Beneath the callus, a light-colored, granular, and irregular growth is visible, surrounded by a thickened, light-colored ring. A distinct groove can be seen between this ring and the body of the plantar wart.

Many dark spots or even streaks accumulate within this yellowish or white mass. They indicate bleeding from small blood vessels inside the plantar wart. These dots or streaks are particularly easy to see when the plantar wart is held up to the light. This is the most distinctive feature for provisionally distinguishing the plantar wart from other potential conditions.

However, the cause of this round, hardened growth may also be another condition. Corns, for example, closely resemble plantar warts in appearance. Corns are simply unsightly accumulations of calloused skin that develop not due to viruses, but as a result of chronic pressure. Calluses also share similar external characteristics. However, unlike plantar warts, calluses alone have a soft, relatively smooth surface and no dark spots.

In very rare cases, what appear to be plantar warts may actually be serious medical conditions. These could include

• a form of cutaneous tuberculosis, a contagious infectious disease, or
• a spinalioma, a form of skin cancer.

However, a definitive diagnosis is only possible after microscopic examination of a tissue sample. Don’t hesitate to see a dermatologist! They can then address your problem specifically and effectively and rule out similar conditions.

A plantar wart grows inward and causes “sharp” pain © David Carillet | AdobeStock

Treatment of plantar warts is strongly recommended, even if they do not cause any symptoms. The underlying viral infection is highly contagious, and proper treatment prevents its spread.

There are various options for reducing and removing plantar warts, and their effectiveness varies from person to person. However, you must not attempt to remove the wart yourself with a sharp object. Bleeding increases the risk of rapid spread to other parts of the body.

The first important step in combating plantar warts is a good, balanced diet. This strengthens the immune system and makes the body more resistant to viruses in the future.

Several over-the-counter remedies are available for self-treatment. However, their use is only recommended if a doctor has ruled out other medical conditions.

Cryotherapy, Self-Treatment, or Surgical Removal

Cryotherapy (cold therapy) is a very popular and proven effective method for treating plantar warts.

Pharmacies carry special ice sticks for applying liquid nitrogen to the affected areas. Using an applicator, the nitrogen is cooled to -50° Celsius and pressed against the plantar wart for about 30 seconds.

The freezing process first causes the upper cells of the plantar wart to die off, which is evident when the affected area turns whiter. Shortly thereafter, the upper layer of the plantar wart can be peeled off.

In most cases, multiple treatments over an extended period are necessary. Only then is there a chance to prevent the plantar wart from recurring and to destroy the papillomaviruses.

Chemical Treatment

Salicylic acid and lactic acid can also reduce plantar warts. Salicylic acid is available in liquid form or pre-applied to pads and is said to be very effective against plantar warts.

This active ingredient softens the inside of the plantar wart and dries out the skin on the surface. The solution can also burn healthy skin. Therefore, you must take care to apply the acid only to the plantar wart itself and protect the surrounding skin. To do this, you can apply a greasy ointment to the healthy skin.

Once the first effects become noticeable, the surface of the plantar wart can be rubbed down with a pumice stone. In this way, the wart can be treated further until it is completely removed.

With salicylic acid, however, there is a risk of bleeding, which could lead to the plantar wart spreading. Lactic acid, on the other hand, has a moisturizing effect.

Salicylic acid- and/or lactic acid-based treatments can be even more effective after a warm foot bath, as the skin will already be slightly softened. Here, too, you should be careful to soak only the foot affected by plantar warts in the water to avoid the risk of spreading the condition to other parts of the body.

Alternatively, you can press a cloth soaked in warm water against the plantar wart for a few minutes.

Surgical Removal

Plantar warts can also be removed through surgery. This was a very common procedure just a few years ago. In this procedure, the plantar wart is scraped off with a “sharp spoon” and thus removed.

This surgical removal can cause heavy bleeding and leave a deep wound that takes a long time to heal.

Therefore, non-invasive treatments are now recommended to minimize the risk of scarring and pain.

However, if the plantar warts keep coming back after initially disappearing, surgical removal can be a safe method for permanently removing the plantar wart.

Laser Therapy

Some doctors have recently begun recommending laser treatment. However, this therapy can also be very painful.

In this procedure, the laser is used to cauterize not the viruses themselves, but the surrounding blood vessels. As a result, the plantar wart is no longer supplied with nutrients and eventually dies off.

Home Remedies

There are also some home remedies that are said to help with plantar warts.

Celandine, also known by the promising name “wart herb,” is a herb that has been used for many years to treat plantar warts.

Tea tree oil, another option, has antibacterial and antiseptic effects on the plantar wart. This is intended to completely prevent the plantar wart from regrowing or leaving a scar. The “all-purpose medicinal plant” aloe vera and the well-known Tiger Balm (an ointment with a high menthol content) are also said to be effective against plantar warts.

There are various measures you should take to prevent plantar warts.

Warts generally develop only when the immune system is compromised. The best prevention is therefore to strengthen the immune system through a balanced diet supplemented by regular exercise and physical activity. The following are also helpful for the immune system:

• getting enough sleep,
• avoiding alcohol, and
• not smoking.

Since the pathogens that cause these warts tend to thrive in warm, moist environments, you should dry your feet thoroughly after washing—including between your toes. Avoid sweaty feet. It’s best to wear lightweight shoes and socks made of breathable materials. This helps prevent plantar warts and athlete’s foot.

Wear shower shoes in public pools and saunas to protect yourself from the virus. Many swimming pools also offer the option to disinfect your feet after swimming. Otherwise, you can carry your own disinfectant spray and use it as needed.

The viruses can also attach themselves to towels or shoes. Therefore, you should not share towels or shoes with other people. 

If you follow these recommendations, you’ll be well protected against painful, unsightly plantar warts. Unfortunately, there’s no guarantee that you’ll be spared from plantar warts.