Iron deficiency anemia is among the most frequent causes of disability. Intravenous iron is the quickest way to correct iron deficiency, bypassing the bottleneck of iron intestinal absorption, the only true mechanism of iron balance regulation in human body. Intravenous iron administration is suggested in patients who are refractory/intolerant to oral iron sulfate. However, the intravenous way of iron administration requires several precautions; as the in-hospital administration requires a resuscitation service, as imposed in Europe by the European Medicine Agency, it is very expensive and negatively affects patient's perceived quality of life. A new oral iron formulation, Sucrosomial iron, bypassing the normal way of absorption, seems to be cost-effective in correcting iron deficiency anemia at doses higher than those usually effective with other oral iron formulations. In this multicentric randomized study, we analyze the cost-effectiveness of intravenous sodium ferrigluconate vs oral Sucrosomial iron in patients with iron deficiency anemia refractory/intolerant to oral iron sulfate without other interfering factors on iron absorption.