Practices and perceptions of 5-aminosalicylic acid use in Crohn's disease: a nationwide survey of physicians in Korea by KASID Guidelines Taskforce Team

Background/Aims: Despite international guidelines recommending against the use of 5-aminosalicylic acid (5-ASA) for Crohn’s disease (CD), it remains widely prescribed. This study aimed to investigate current patterns of 5-ASA use and physicians’ perceptions of its efficacy among Korean specialists. Methods: A nationwide online survey was conducted in August 2025 targeting Korean gastroenterologists and colorectal surgeons managing inflammatory bowel disease. The questionnaire included 19 items addressing prescribing behaviors, perceived efficacy, and clinical decision-making regarding 5-ASA in CD. Results: A total of 118 out of 124 physicians (95.2%) responded to the survey. The majority (67.8%) reported prescribing 5-ASA to more than half of their patients with CD. Standard to high doses (> 2 g/day) were commonly used (94.9%), and time-dependent formulations were preferred (92.4%). Although 55.1% used 5-ASA irrespective of disease location, it was frequently prescribed for colonic/ileocolonic disease (57.7%). Physicians primarily used 5-ASA in cases of non-active or mildly active CD. Notably, over 70% of respondents perceived 5-ASA to have a marginal yet beneficial effect on clinical remission, biomarker improvement, and mucosal healing. Approximately one-third of physicians reported continuing 5-ASA even after initiating biologics or small molecules. Conclusions: This survey reveals a substantial gap between clinical guidelines and current practice in Korea regarding 5-ASA use for CD. Many physicians continue to view 5-ASA as a relevant option, particularly for patients with low inflammatory burden. These discrepancies likely reflect practical factors such as clinical experience and drug characteristics, which should be carefully considered before excluding 5-ASA from CD management.