Suggest Treatment Fro Sun Poisoning

Hi, I have had what I believe is sun poisoning for a few days now, and it only seems to be getting worse. I am experiencing dehydration, weakness, chills, nausea, and my skin on my back specifically is not only blistering/peeling off in large sections but it is so raw that it is starting to crack in certain places. I saw a doctor and he gave me steroids for a few days, but they do not seem to be helping. I am at a loss for what else to do and I am wondering if I should go to a hospital immediately?