Oral iron therapy in inflammatory bowel disease: Usage, tolerance, and efficacy

Background: Iron deficiency is common in inflammatory bowel disease (IBD). Anecdotal evidence suggests that oral iron is poorly tolerated and may exacerbate disease activity in patients with IBD. Aim: The aim of this study was to retrospectively compare usage, tolerance, and efficacy of oral iron therapy in patients with IBD and noninflammatory causes of iron deficiency. Methods: Case records of 277 patients with IBD and 24 non-IBD iron-deficient control patients covering a 4-year period were retrospectively analyzed. Results: Fifty-three of 277 (19%) of the patients with IBD studied had received oral iron. In only 40% of the patients who had IBD and 63% of the patients who did not (p = not significant) was iron deficiency formally confirmed before treatment. Intolerance to iron was reported in only 25% of the patients who had IBD and 17% of the patients who did not (p = not significant). In only two of eight adequately monitored iron-intolerant patients with IBD was iron therapy associated with an increase in inflammatory markers. When formally checked, iron repletion was successfully achieved as frequently in patients who had IBD (59%) as in patients who did not (45%). Conclusion: Iron therapy is often used without a formal diagnosis of iron deficiency having been made, at least in part because of the difficulty in making this diagnosis using ferritin, an acute-phase protein. Patients with IBD are no more intolerant of oral iron than other patients and have similar rates of repletion.