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Alternate Day vs. Daily Iron Supplementation in Iron Depleted Women

Comparing Oral Iron Supplementation Using Alternate-day Dosing to the Standard of Care Consecutive-day Dosing in Iron-depleted Women With or Without Mild Anemia

Status
Completed
Phases
NA
Study type
Interventional
Source
ClinicalTrials.gov
Registry ID
NCT05105438
Enrollment
150
Registered
2021-11-03
Start date
2021-12-16
Completion date
2022-12-08
Last updated
2024-01-24

For informational purposes only — not medical advice. Sourced from public registries and may not reflect the latest updates. Terms

Conditions

Iron-deficiency, Iron Deficiency Anemia

Keywords

iron supplementation, dosing regimen, iron sulfate, women of reproductive age

Brief summary

Iron deficiency (ID) with or without anemia is a major public health problem worldwide, especially in women of reproductive age. Iron supplementation can be an effective strategy to prevent and treat ID and iron deficiency anemia (IDA). Recent studies suggests that giving oral iron every other day would be an optimized dosing regimen with maximized absorption and a lower incidence of gastrointestinal side effects compared to consecutive day dosing. Long-term trials in which participants and investigators are blinded to the dosing interval with iron status and gastrointestinal side effects as study outcomes are needed.

Interventions

DIETARY_SUPPLEMENTConsecutive Day Dosing

100 mg iron as FeSO4 daily for 3 months, followed by matched placebo daily for 3 months.

DIETARY_SUPPLEMENTAlternate Day Dosing

100 mg iron as FeSO4 and matched placebo on alternating days for 6 months.

Sponsors

Swiss Federal Institute of Technology
Lead SponsorOTHER

Study design

Allocation
RANDOMIZED
Intervention model
PARALLEL
Primary purpose
TREATMENT
Masking
DOUBLE (Subject, Investigator)

Masking description

double-blinded randomized controlled study: participants and investigators are blinded

Eligibility

Sex/Gender
FEMALE
Age
18 Years to 45 Years
Healthy volunteers
Yes

Inclusion criteria

* Female, 18 to 45 years old, * SF levels \<25 μg/L, * Hb levels ≥ 11 g/dL * Normal Body Mass Index (18.5-25 kg/m2), * In possession of a mobile phone on which the study app can be loaded, * Signed informed consent, * Not mandatory (only for subgroup analysis): having participated in a former stable iron isotope study in our laboratory between 1-5 y ago

Exclusion criteria

* Elevated CRP \> 5 mg/L, * Any metabolic, gastrointestinal, kidney or chronic disease (self-reported) affecting iron metabolism, * Continuous/long-term use of medication, which may interfere with iron absorption, gut physiology and iron metabolism, * Consumption of additional iron supplements over the study period, * Consumption of iron supplements since screening, * Difficulties with blood sampling, * Known hypersensitivity or allergy to iron or placebo capsules in the given amount (ferrous sulfate, mannitol, silica) * Pregnancy, breastfeeding * Women who intend to become pregnant during the course of the study, * Known or suspected non-compliance, drug or alcohol (more than 2 drinks/day) abuse, * Smokers (\> 1 cigarette per week), * Participant is likely to be absent on one the study appointments, * Inability to follow the procedures of the study, e.g. due to language problems, self-reported psychological disorders, etc. of the participant.

Design outcomes

Primary

MeasureTime frameDescription
Serum Ferritin (SF)Day 93in consecutive day group
Event rate of GI side effectsDay 90in consecutive day group

Secondary

MeasureTime frame
Serum Transferrin Receptor (sTfR)Day 0
Total iron binding capacity (TIBC)Day 0
Serum Iron (SFe)Day 0
C-Reactive Protein (CRP)Day 0
Alpha-1-acid Glycoprotein (AGP)Day 0
Intestinal Fatty Acid-binding Protein (I-FABP)Day 0
CalprotectinDay 0
Hemoglobin (Hb)Day 0
Event rate of GI side effectsDay 90
Incidence of GI side effectsDay 90
Event proportion of GI side effectsDay 90
Severity of GI side effectsDay 90
Fecal blood lossesDay 0
Iron absorption from supplementsDay 90
HepcidinDay 0
Serum Ferritin (SF)Day 0

Countries

Switzerland

Outcome results

None listed

Source: ClinicalTrials.gov · Data processed: Feb 10, 2026