Hello, I am Dr. Raksmey. Thank you for your question. Frozen therapy (cryotherapy) by using very cold substance( usually liquid nitrogen). Cryotherapy is a standard treatment for warts. Cryotherapy is painful. A numbling local anesthetic is usually not needed but may be used in some cases. Most warts require 1 to 4 treatments, with 1 to 3 weeks between each treatment. If Cryotherapy is to the skin overlying a nerve (such as on finger) there may be some numbness to the area. This nearly always returns within a few weeks or months. You should looking after the treatment area, they may have blister within a few hour. Within a few day dry crust forms, but usually no special attention is needed during the healing phase. For the hand the crust is pealing off up to 3 weeks. Secondary infection is uncommon but sign to watch for are: pain, swelling, pus or redness around the treatment area. Some patients experience pain at the site of treatment. This can usually better from paracetamol or Ibuprofen. Consult your Doctor if you are concerned. Cryotherapy has been shown to have a high success rate in permanently skin growths. Prevention wart: you should avoid share towel with a person who has warts, avoid direct contact with another person s wart, do not share shoes or sock with someone who has planta warts.... I hope it help you. If you have another question let discuss more. Regards, Dr. Raksmey