An anaphylactic reaction after intravenous Fe injection (Ferrum Hausmann) occurred in an 84-year-old female patient on treatment for iron deficiency anemia. After emergency admission to hospital, it emerged that she suffered an acute anteroseptal myocardial event, but could be mobilized without any problems on adequate cardiac medication. After ruling out any hyporegenerative pathology, the hemoglobin level of 101 g/L registered can probably be explained within the scope of mild renal insufficiency. Instead of the intravenous form of iron (III) sucrose (saccharate) complex (Ferrum Hausmann i.v. / Venofer), the attending general practitioner had administered parenteral iron replacement i.v. in the form of Ferrum Hausmann (iron (III) hydroxide dextran complex), which is intended for intramuscular administration. This is the reason why, firstly, the oral form of administration should be preferred over the parenteral and, secondly, parenteral replacement using the iron saccharate complex should be only initiated in the case of a pathological oral iron load test indicating an iron resorption disorder.