Since the introduction of anti-tumor necrosis factor (TNF) therapy as treatment of inflammatory bowel disease (IBD), care of pediatric and adult patients with IBD has significantly improved. To further improve treatment efficacy and durability, multiple trials have compared the efficacy of combination therapy, using anti-TNF therapy combined with an immunomodulator (a thiopurine or methotrexate), with that of anti-TNF monotherapy with contradicting results. The safety of combined therapy has been questioned after several reported cases of hepatosplenic T-cell lymphoma in young patients with IBD so treated. Physicians prescribing anti-TNF therapy to patients with IBD are required to weigh the benefits of combined therapy with its risks. To inform physicians treating children with IBD of these benefits and risks, we reviewed studies in pediatric and adult patients with IBD comparing efficacy, durability, and/or safety of combined therapy with anti-TNF monotherapy.