What is the treatment for iron deficiency?

Treatment of Iron Deficiency

The first-line treatment for iron deficiency should be oral iron supplementation with ferrous sulfate 200 mg once daily (containing approximately 65 mg of elemental iron), which should be continued for approximately 3 months after normalization of hemoglobin levels to ensure adequate repletion of iron stores. 1, 2

Oral Iron Therapy

• Ferrous sulfate is the most simple, effective, and cost-efficient oral iron preparation, typically dosed at 200 mg twice daily 2
• Alternative ferrous salt preparations like ferrous gluconate and ferrous fumarate are equally effective and may be better tolerated by some patients 1, 3
• An expected hemoglobin rise of approximately 2 g/dL should occur after 3-4 weeks of treatment 2, 1
• Treatment should continue for 3 months after the iron deficiency has been corrected to ensure iron stores are replenished 2, 1
• Lower doses may be as effective and better tolerated in patients who experience gastrointestinal side effects 2, 1
• Taking iron on alternate days may improve absorption while reducing side effects 1, 4
• Ascorbic acid (250-500 mg twice daily with iron) may enhance iron absorption, though evidence for effectiveness is limited 2, 1

Dosing Considerations

• Standard ferrous sulfate tablets contain 324 mg of ferrous sulfate, equivalent to 65 mg of elemental iron 5
• For iron deficiency anemia, doses of 60-120 mg/day of elemental iron are recommended based on severity 2
• For pregnant women, start with oral, low-dose (30 mg/day) supplements of iron at the first prenatal visit 2
• If anemia is diagnosed during pregnancy, increase to 60-120 mg/day of elemental iron 2

Intravenous Iron Therapy

• Intravenous iron should be considered as first-line treatment in specific situations: 2, 1

  • Patients with clinically active inflammatory bowel disease
  • Patients with previous intolerance to oral iron
  • Patients with hemoglobin below 10 g/dL
  • Patients who need erythropoiesis-stimulating agents
  • Patients with poor absorption (celiac disease, post-bariatric surgery)
  • Patients with chronic inflammatory conditions

• Several IV iron preparations are available: 2

  • Iron sucrose (maximum single dose 200 mg over 10 minutes)
  • Ferric carboxymaltose (maximum single dose 1000 mg over 15 minutes)
  • Iron dextran (maximum single dose 20 mg/kg over 6 hours)

• The risk of serious reactions with modern IV iron formulations is very low (<1:250,000 administrations), but resuscitation facilities should be available 2

Monitoring and Follow-up

• Monitor hemoglobin levels within 4 weeks to assess response to therapy 1, 4
• Once normal, the hemoglobin concentration and red cell indices should be monitored at intervals - suggested 3 monthly for 1 year, then after a further year 2, 1
• Failure to respond to oral iron therapy (no increase in Hb by 1 g/dL or Hct by 3% after 4 weeks) should prompt further evaluation 2, 4
• To measure success of IV iron treatment, basic blood tests should be repeated after 8-10 weeks, not earlier, as ferritin levels are falsely high immediately after infusion 2

Common Pitfalls to Avoid

• Discontinuing iron therapy too early before iron stores are replenished 2, 1
• Using parenteral iron as first-line therapy when oral iron would be effective 1
• Not investigating the underlying cause of iron deficiency, especially in men and postmenopausal women 2, 4
• Overlooking potential gastrointestinal blood loss in men and postmenopausal women with iron deficiency 4, 6
• Failing to adjust iron therapy in patients with inflammatory conditions where standard markers of iron status may be misleading 2