Iron Absorption following a Single Oral Dose of Ferrous Sulfate or Ferric Gluconate in Patients with Gastrectomy

Background: Iron deficiency anemia frequently occurs in gastrectomized patients. Methods: Serum iron levels following the ingestion of a single oral dose of 105 mg elemental iron, taken as ferrous sulfate (FeS) or ferric gluconate (FeG), have been evaluated in 20 gastrectomized patients (and 20 controls). All subjects participated on 2 different test days, 1 month apart: they took a single dose of 105 mg elemental iron as FeS or FeG after a night of fasting. Serum iron concentrations at baseline, 30, 60, 120 and 180 min after the oral dose administration were measured. Results: In patients and controls receiving FeG, serum iron levels did not significantly change. After oral ingestion of FeS, patients' serum iron levels gradually increased. The increase in serum iron levels was 148 and 168% at 120 and 180 min in patients (p < 0.0001 for both evaluations), whilst in controls, it was 216% at 120 min and 234% at 180 min, i.e. significantly higher than in gastrectomized patients (p < 0.001 for both evaluations). Conclusions: In gastrectomized patients, a single oral dose of FeS shows a significant increase in iron serum concentration, albeit lower than in controls. Further studies on a larger sample of patients will be necessary to confirm these results.