For decades, thiopurines have been the mainstay of inflammatory bowel disease (IBD) treatment and will play an important role in the future. However, complex metabolism and various side effects limit the use of these potent drugs in clinical practice. The Korean Association for the Study of Intestinal Diseases developed a set of consensus statements with the aim of guiding clinicians on the appropriate use of thiopurines in the management of IBD.

Sixteen statements were initially drafted by five committee members. The quality of evidence and classification of recommendation were assessed according to the Grading of Recommendations Assessment, Development and Evaluation system. The statements were then circulated to IBD experts in Korea for review, feedback, and then finalized and accepted by voting at the consensus meeting.

The consensus statements comprised four parts: (1) pre-treatment evaluation and management strategy, including value of thiopurine S-methyltransferase screening, dosing schedule, and novel biomarkers for predicting thiopurine-induced leukopenia; (2) treatment with thiopurines with regards to optimal duration of thiopurine treatment and long-term outcomes of combination therapy with anti-tumor necrosis factors; (3) safety of thiopurines, especially during pregnancy and lactation; and (4) monitoring side effects or efficacy of therapy using biomarkers.

Thiopurines are an effective treatment option for patients with IBD. Management decisions should be individualized according to the risk of relapse and adverse events.