Warts are common, non-cancerous skin growths caused by the human papillomavirus (HPV) that can appear almost anywhere on the body. These growths result from a rapid increase in cell production on the skin’s outer layer. Because warts can be persistent, disfiguring, or cause discomfort, cryotherapy is a common and effective removal method. This process involves freezing the affected tissue using an extremely cold agent, typically liquid nitrogen, to destroy the wart cells and encourage the growth of healthy new skin.
The Sensation During Freezing
The immediate experience of having a wart frozen is often described as an intense sensation of cold that quickly transitions into stinging or burning. This discomfort is caused by the rapid temperature drop as the liquid nitrogen, which is around -320°F, contacts the skin surface. The application itself is brief, usually lasting between 10 and 20 seconds, and the sharpest sensation occurs during this short window.
As the treated area begins to thaw immediately after the application is stopped, the sensation can shift to a hot or aching feeling, similar to a localized frostbite injury. The level of discomfort experienced is highly dependent on the wart’s location. Thicker or deeply embedded growths, such as plantar warts on the foot, generally cause more intense pain. While the freezing process can be uncomfortable, the most severe pain sensation is fleeting, lasting only a few minutes before subsiding.
What Happens Immediately After the Treatment
Following the cryotherapy session, it is normal for a localized reaction to develop, which can include redness and swelling around the treated site. Within a few hours to a day, a blister will typically form underneath the treated wart tissue, signaling the body’s inflammatory response to the cell damage. This blister acts as a protective barrier and may be clear, or sometimes appear dark purple or black if small blood vessels were also frozen, creating a blood blister.
The area is likely to feel sore or tender, manifesting as a dull ache or throbbing sensation that may persist for several hours or even a full day. Over-the-counter pain relievers, such as acetaminophen or ibuprofen, are generally sufficient to manage this residual discomfort. The blister will usually flatten and begin to dry out within a few days, forming a hard scab or crust over the next week.
It is important to leave the scab intact, as it shields the new skin growing underneath. Picking at the scab can lead to infection or scarring. The dead wart tissue eventually falls off along with the scab, which can take anywhere from one to four weeks depending on the wart’s size and location.
How Cryotherapy Works to Remove Warts
Cryotherapy works by introducing a massive thermal shock to the wart cells, causing their destruction through two primary mechanisms. The first is the rapid extraction of heat by liquid nitrogen, which leads to the formation of ice crystals inside the wart cells. These microscopic ice crystals physically pierce and rupture the cell membranes, directly causing cell death, a process known as necrosis.
The extreme cold also affects the delicate network of small blood vessels that supply the wart, causing them to constrict and become damaged. This vascular injury cuts off the blood flow to the infected tissue, resulting in tissue ischemia. This process further promotes the death of the wart, allowing healthy skin to regenerate.