There are cases where parenteral iron is preferable over oral iron. These are cases where oral iron is not tolerated, where the haemoglobin needs to be increased quickly (e.g. post partum, post operatively, post transfusion), where there is an underlying inflammatory condition (e.g. inflammatory bowel disease) or renal patients, the benefits of parenteral iron far outweigh the risks. In many cases, use of intravenous iron such as ferric carboxymaltose has lower risks of adverse events than a blood transfusion and as long as the person is stable is a better alternative. Ultimately this always remains a clinical decision based on local guidelines, although National Guidelines are increasingly stipulating IV iron in certain groups of patients.