The primary purpose of the project is to determine what is the best schedule for restarting infliximab in patients with inflammatory bowel disease (IBD) specifically ulcerative colitis and Crohn's disease, who have undergone infliximab infusions before. The primary endpoint would be the failure rate; the need to discontinue infliximab or change treatment. A secondary aim will be to determine if infliximab drug and antibody levels can predict clinical outcomes at 1 year. Other secondary outcomes include comparing short-term and long-term steroid free remission rate, and serum and fecal inflammatory markers in response to infliximab.