What is the management of iron deficiency anemia?

Management of Iron Deficiency Anemia

The first-line treatment for iron deficiency anemia is oral iron supplementation with ferrous sulfate 200 mg three times daily, which should be continued for three months after hemoglobin normalization to adequately replenish iron stores. 1, 2

Oral Iron Therapy

• Ferrous sulfate 200 mg three times daily (providing approximately 65 mg of elemental iron per tablet) is the most simple, effective, and inexpensive treatment option 1, 2, 3
• Alternative oral preparations include ferrous gluconate and ferrous fumarate, which are equally effective and may be better tolerated by some patients 1, 2
• Liquid preparations may be tolerated when tablets are not 1
• Add vitamin C (ascorbic acid) to enhance iron absorption, especially when response to therapy is poor 1, 2
• Hemoglobin should rise by approximately 2 g/dL after 3-4 weeks of treatment 1, 2
• Continue treatment for three months after correction of anemia to adequately replenish iron stores 2

Monitoring Response

• Failure to respond to oral iron therapy (hemoglobin not rising by 2 g/dL after 3-4 weeks) is usually due to:
  • Poor compliance
  • Misdiagnosis
  • Continued blood loss
  • Malabsorption 1, 2
• Resolution of anemia should be achieved in 80% of patients by six months 1
• Monitor hemoglobin and red cell indices regularly during treatment and for up to two years after normalization 2

Parenteral Iron Therapy

• Reserve intravenous iron for patients with:
  • Intolerance to at least two oral iron preparations
  • Non-compliance with oral therapy
  • Malabsorption
  • Conditions where oral iron is unlikely to be absorbed (e.g., active inflammatory bowel disease)
  • Failure to improve ferritin levels despite adequate oral iron trial 1, 2
• Intravenous iron formulations that can replace iron deficits with 1-2 infusions are preferred over those requiring multiple infusions 1
• While all IV iron formulations carry similar risks, true anaphylaxis is very rare; most reactions are infusion-related pseudo-allergies 1

Special Populations

• Inflammatory Bowel Disease:

  • Treat active inflammation to enhance iron absorption
  • Use intravenous iron in patients with active inflammation and compromised absorption 1

• Bariatric Surgery Patients:

  • Intravenous iron therapy is recommended due to disrupted duodenal iron absorption 1

• Portal Hypertensive Gastropathy:

  • Start with oral iron supplements
  • Consider intravenous iron for ongoing bleeding unresponsive to oral therapy
  • Consider nonselective β-blockers to treat portal hypertension 1

• Celiac Disease:

  • Ensure adherence to a gluten-free diet to improve iron absorption
  • Add iron supplementation based on severity of deficiency 1, 2

• Menstruating Women:

  • Iron deficiency occurs in 5-10% of menstruating women 1, 2
  • Common causes include menorrhagia, pregnancy, and breastfeeding 2
  • Women under 45 years without GI symptoms may not require extensive GI investigation 1

Common Pitfalls and Caveats

• Discontinuing therapy prematurely due to gastrointestinal side effects without trying alternative formulations 2
• Using parenteral iron as first-line therapy when oral iron would be appropriate 1, 2
• Not investigating the underlying cause of iron deficiency, especially in patients >45 years old 1, 2
• Not considering malabsorption in patients with poor response to oral iron 2, 4
• Failing to continue treatment long enough to replenish iron stores after hemoglobin normalization 2
• Administering divided daily doses when alternate-day dosing may improve absorption and reduce side effects 5