Infliximab (IFX) is highly effective in inducing and maintaining remission in patients with inflammatory bowel disease (IBD). However, a large proportion of patients will eventually lose response to IFX. Therefore, strategies to improve the outcome of maintenance treatment with IFX are required. Retrospective analyses suggest that adjusting IFX treatment in order to achieve IFX trough levels (TL) above a well-defined therapeutic threshold will improve the outcome of IFX treatment.