Cryotherapy is a simple office procedure utilizing liquid nitrogen, delivered by a special tip application, to freeze epidermal lesions. Liquid nitrogen is considered a surgical destruction of lesions, that uses a freeze/thaw cycle for 30 seconds. After the treatment, the lesion will swell for a few hours to days, then scab and eventually it should fall off. The entire process can take anywhere from one to three weeks to see the result. Often the lesion may need to be treated again in 20 to 30 days.