Curbside Consultation in IBD: 49 Clinical Questions, Second Edition

David T Rubin, MD; Sonia Friedman, MD; Francis A Farraye, MD MSc

Question 17: How Long Do You Wait Before Declaring Treatment Failure With Azathioprine/6-Mercaptopurine, And Do You Ever Consider Stopping Therapy With These Agents After A Period Of Time? (continued)

Julian Panes, MD, PhD; Elena Ricart, MD, PhD

Physicians commonly assume that one of the limitations of the clinical use of azathioprine (AZA) and 6-mercaptopurine (6-MP) in the management of active inflammatory bowel disease (IBD) is their delayed onset of action. A Cochrane collaboration meta-analysis1 showed that administration of AZA or 6-MP during 17 weeks or longer increases response rates, and, based on this observation, it was recommended that efficacy of thiopurines for treatment of IBD should be evaluated only after 3 to 5 months of treatment to achieve the maximum benefit.2,