Thiopurines are widely used, for prolonged periods, as maintenance treatment in Crohn’s disease and ulcerative colitis. Some safety concerns including blood toxicity, immunoallergic reactions, and teratogenicity have been recognized since the early development of these drugs. These established safety issues are updated in the present review. New risks including liver toxicity, opportunistic infections, and non-melanoma skin cancers have more recently been identified and quantified through post-marketing observational studies. These are also detailed here, along with their consequences in clinical practice.
Inflamm Bowel Dis Monit 2010;10(4):117–25.