Cryotherapy is the use of extreme cold to treat skin lesions. It is used for the treatment of benign (non-cancerous), pre-cancerous and low grade certain cancerous lesions. Liquid nitrogen is the preferred cryogen, which is usually sprayed onto the treatment area until the desired degree of freezing has occurred. This results in a ‘frost bite’ type injury to the lesion. Initially the treated spots will look red and then may blister and scab.