Approach to 25(OH)D supplementation in patients with IBD Approach to 25(OH)D supplementation in patients with IBD. Determining adequate daily dose as (target s-25(OH)D level – current s-25(OH)D level) µg. Approach to 25(OH)D supplementation in patients with IBD. Determining adequate daily dose as (target s-25(OH)D level – current s-25(OH)D level) µg. If target level is not reached within 3 months, administration as weekly bolus should be tried. If current level continues <target level, malabsorption should be considered. CRP, C reactive protein; HBI, Harvey Bradshaw Index; IBD, inflammatory bowel disease; UCDAI, Ulcerative Colitis Disease Activity Index. Ole Haagen Nielsen et al. Frontline Gastroenterol doi:10.1136/flgastro-2018-101055 Copyright © BMJ Publishing Group Ltd & British Society of Gastroenterology. All rights reserved.