Dealing w/ AIH and Cellcept and its effects of weight gain

Okay hears the deal I was put on prednison when I was 17yrs old along with imuran, now i know the effects of prednison obviouly, it being a steroid there usually are some weight gain and moon face etc as common side effects. Now I'm 19yrs old and they have me on cellcept. I have always been extremely active even to due to my fatigue but I cannot loose a pound, I will work out 24-7 and change my diets often to see if anything changes and...nothing. I haven't really been able to loose the weight from the prednison, and I will gain then maintain that weight then then gain a little more and maintain. I have been noticing not only from the last past year i have been having food sensitivities my face with blow up from eating things with hight salt content like cereal, ice cream, or even dressings on salads. So if anyone is having any of these similar problems and has some idea about how to handle it, that would be great. I just would love to be back to my regular weight and feel great.