Liquid nitrogen freezing will have certain painful and uncomfortable symptoms, the temperature of liquid nitrogen is below -196 ℃, liquid nitrogen freezing treatment method is to apply liquid nitrogen to the affected area, through the very low temperature of the lesion will be frostbite destroyed, so as to achieve the purpose of treatment. In the process of treatment, the local nerve endings of the lesion and the surrounding normal tissue may be frozen, so there will be a certain amount of pain and discomfort, some patients will also appear in the local frostbite caused by blisters, the pain caused by this situation is generally not too serious, so do not worry too much. The current liquid nitrogen cryotherapy is widely used to treat flat warts, neurodermatitis, chronic eczema, lichen planus, seborrheic dermatitis and so on. For patients who have diabetes or are old and frail, tolerance may be relatively poor and is generally not recommended.