My father has been diagnosed recently with exfoliative erythroderma, they put him on an immune suppressant i'm not quite understanding the reasoning for this...also, treatment options seem to be far and few between do you have any knowledge on this particular disease/disorder...? He is 47 years of age and has been suffering from this for around 4 years now. He is so cold all the time. I just want to find him help

Summarized question: What is exfoliative erythroderma?