I'm not sure if this has been addressed here before or not, but I very recently heard about an antidepressant that has some hope for IBD - the test was on mice and the colitis was chemically induced, but the results were favorable. The medicine is desipramine - you can google it and ulcerative colitis for more information on the study. I learned about this on a different IBD board and don't know anything else about it than that, but the person who told me about it had a friend with UC that was taking it and it was helping both his UC and depression/anxiety.
Here is a study about it: http://jpet.aspetjournals.org/cgi/content/abstract/jpet.108.141259v1
Mom of Son 17 UC dx 07/02, Sulfasalazine, Imuran, Cortafoam, folic acid, L. Reuteri, Culturelle, Zyrtec, Iron, Vit/Min
Daughter 9 UC dx 08/07 Colazal, 6MP, Iron, Vit/Min., Culturelle