BACKGROUND Anemia in the elderly is a common clinical finding. Prevalence in hospitalized geriatric patients approximates up to 40% presenting as iron deficiency anemia associated with absolute iron deficiency, anemia of chronic disease associated with functional iron deficiency or unexplained anemia. In patients with functional iron deficiency oral iron substitution is ineffective due to elevated hepcidin levels, such as in renal anemia. In these patients intravenous iron substitution represents a cornerstone. However, data among geriatric patients are limited. We conducted three non-interventional studies collecting data with respect to efficacy and tolerance of ferric carboxymaltose (ferinject) in three patient groups (cancer, chronic kidney disease [CKD], chronic inflammatory bowel disease [CIBD]) with anemia and functional iron deficiency. The present sub-analysis describes the results among the geriatric patients (age > 70 years) observed in all three observational studies. PATIENTS, METHODS 264 patients were analyzed (mean age of 76.9 years [70-90 years; SD +/- 5.2 years]). Patients received an average amount of 1200 mg ferric carboxymaltose (746-1575 mg). RESULTS Hemoglobin levels (p < 0.001), serum ferritin (p < 0.001) and transferrin saturation (p < 0.05) rose significantly in CKD patients; in CIBD patients hemoglobin and transferrin saturation rose significantly (p < 0.05) while the rise of ferritin failed to be significant. In oncologic patients the rise of hemoglobin and ferritin levels was of high statistic significance (p < 0.001) and transferrin saturation also rose significantly (p = 0.02) Fatigue, mental capacities as well as dyspnea improved among CKD-and CIBD-groups. No severe adverse reactions occurred. CONCLUSION Administration of ferric carboxymaltose in geriatric patients is well tolerated and offers an effective treatment option for the treatment of functional iron deficiency.