Daily versus alternate-day oral iron in women with iron deficiency anemia: impact of dosing schedule and adherence on hemoglobin recovery.

Introduction: Iron deficiency anemia (IDA) is common among women of reproductive age and is frequently associated with abnormal uterine bleeding (AUB). Although oral iron is first-line therapy, the optimal dosing schedule remains uncertain. This study compared daily and alternate-day oral iron in real-world practice. Materials and methods: We conducted a prospective observational cohort study of women aged 18-70 years with confirmed IDA treated with oral ferrous sulfate at a tertiary referral center between January 2023 and June 2024. Patients received oral iron every 24 h or every 48 h according to physician prescription. AUB etiology was classified using the PALM-COEIN system. Outcomes included hemoglobin change, World Health Organization anemia severity, hemoglobin normalization (≥12 g/dL), adherence, adverse-event-related discontinuation, and intravenous iron escalation. Results: A total of 171 women were included. Leiomyomas were the most frequent PALM-COEIN category (106 patients, 62.0%). Mean baseline hemoglobin was 9.02 ± 1.45 g/dL. At 6 weeks, mean hemoglobin was 10.91 ± 1.76 g/dL in the 24-h group and 11.26 ± 1.86 g/dL in the 48-h group ( Conclusion: Both regimens were associated with hematologic improvement. However, because allocation was non-randomized, baseline differences were present, and intravenous iron escalation was not based on standardized criteria, equivalence cannot be inferred. Oral iron dosing should be individualized.