Inflammatory bowel disease (IBD), consisting of two major forms, Crohn's disease (CD) and ulcerative colitis (UC), affects more than 1.6 million people in the United States alone. Though the precise mechanisms underlying the inflammation and immune responses in IBD are still being investigated, various inflammatory mediators, including pro-inflammatory cytokines, and genes have been implicated in the disease process. At present, there are no reliable mechanisms to predict response to individual IBD medications. The investigators seek to evaluate whether inflammatory cytokines change longitudinally during treatment with anti-cytokine agents in both treatment primary responders and primary non-responders. In addition, the investigators will be evaluating the pharmacogenetics of treatment response to these agents.