Correcting iron deficiency

Iron deficiency is the most common cause of anaemia. It has many different causes, so further investigations are required to establish an underlying aetiology. An iron study is the first-line investigation and includes serum iron, ferritin, transferrin and transferrin saturation. Serum ferritin is normally a suitable indicator of iron stores but can be increased by inflammation to an extent that makes the ferritin unreliable for assessment of iron deficiency. Oral iron replacement is the most appropriate first-line treatment in the majority of patients. Its efficacy can be limited by poor patient compliance due to the high rate of gastrointestinal adverse effects and the prolonged treatment course needed to replenish body iron stores. Intravenous iron preparations are indicated when oral iron therapy has failed or rapid replenishment is required. Ferric carboxymaltose can rapidly deliver a large dose of iron, making it the preparation of choice for outpatients. Despite their excellent safety profiles, all intravenous iron preparations carry the risk of anaphylaxis. Patients require monitoring and access to resuscitation facilities.