Refractory inflammatory bowel disease (IBD) can be defined as persistent acute symptomatic disease despite anti-inflammatory therapy or as chronically active disease requiring continuous treatment for relief of symptoms. Treatment options include azathioprine (AZA), 6-mercaptopurine (6-MP), methotrexate (MTX), cyclosporine (CYA), and experimental therapies that are cytokines or cytokine antagonists. AZA and 6-MP have identical actions in IBD. 6-MP is effective in about 75% of patients with inflammatory Crohn's disease. The mean time until the onset of action is 3.1 months. AZA is effective in ulcerative colitis as a steroid-sparing agent. Side-effects occur in 10-15% of patients on AZA or 6-MP for IBD. MTX induces symptomatic remission in about 40% of patients with Crohn's disease. The potential for hepatic fibrosis from MTX is a concern. CYA appears effective in the acute management of severe ulcerative colitis. CYA has not proven useful in the long-term management of Crohn's disease. Potentially serious side-effects include hypertension and renal insufficiency. The cytokine antagonist, anti-tumor-necrosis-factor-alpha antibody, and the anti-inflammatory cytokine, interleukin 10, appear promising for the treatment of Crohn's disease.