Would Slippery Elm help my daughter?

My daughter is 17 and has ulcerative colitis. She was diagnosed when she was 10. She's had bad reactions to both mesalamine and sulfasalazine. She's on steroids right now for a flare-up, and while it's getting better, it's still there. We've been reading about home remedies, and we read about slippery elm. She's really excited to try it, but I've also read that if you're sensitive to salicylates, that you shouldn't use slippery elm, and sulfasalazine is part salicylate.

Has anyone who is sensitive to salicylates tried slippery elm? Did it help? Which form is best, tablet or powder? Any help would be greatly appreciated!