What should I expect if I have liquid nitrogen treatment for DSAP?

Liquid nitrogen can be used to freeze off lesions resulting from disseminated superficial actinic porokeratosis (DSAP). When DSAP is first diagnosed, a person with the disorder may have 30-40 lesions that are treated with liquid nitrogen several times. 

During this procedure, the doctor quickly sprays liquid nitrogen on each skin lesion, leaving a white mark. This may cause a stinging sensation. You will experience mild pain for about 30 minutes, depending on how widespread the area on the arms and legs might be. You probably won't require pain medication.

Over the next few hours, blisters appear. They look like tight brownish bubbles and they should not be broken on purpose. Breaking the blisters might expose the skin to infection. The body should be allowed to reabsorb the fluid over the next week or so. At that time, small brown scabs will form and will eventually flake off by themselves. Loose-fitting pants and shirts can easily protect the skin and hide the blisters.