I have done some sucessfull work with a little boy with exczema. I did not use a script rather we talked about what exczema felt like, and if he could think of an image that would make the itching stop (that was his primary concern) he came up with visualising his exczema as ants running over his feet, and getting rid of the itch by putting on ant powder and then running his feet under a cold tap. We induced hypnosis with a story telling method, he chose that his 'walk in his mind' would be through a jungle. I walked him through the jungle, got him to notice the ants on his feet then to put on the ant powder, and wash it off under a cold tap, I got him to notice how this had made his feet stop itching, and talked about him being able to stop the itching in this way whenever he chose too.
When we had our next session he reported being able to completely control the itching. At this session we talked about the skin being a very sensitive part of the body, showing up upsets, both physical and of the mind, ideomotor responses had suggested that his exczema was related to emotional responses, therefore in this session we regressed to cause and released the trapped emotions, guided his imaginative part into finding other ways to express emotions safely, and suggested that from now on he would be abler to use these other methods and hence would no longer need to show his emotions in his skin.