What is the recommended management for iron deficiency anemia?

Management of Iron Deficiency Anemia

The recommended first-line treatment for iron deficiency anemia is oral iron supplementation with ferrous sulfate 324 mg (65 mg elemental iron) once daily, with alternative-day dosing as an option for improved tolerability. 1

Diagnosis of Iron Deficiency Anemia

Iron deficiency anemia diagnosis is based on ferritin levels:

• Ferritin <30 μg/L: Definitive iron deficiency
• Ferritin 30-100 μg/L with transferrin saturation <20%: Possible iron deficiency, especially with inflammation
• Ferritin >100 μg/L with normal transferrin saturation: Iron deficiency is unlikely 1

Treatment Algorithm

First-Line Treatment: Oral Iron Therapy

• Dosage:

  • Ferrous sulfate 324 mg (65 mg elemental iron) once daily 1
  • Alternative options: ferrous gluconate and ferrous fumarate are equally effective 2
  • For improved tolerability: alternate-day dosing may be more effective than daily dosing 1, 3
  • Morning dosing is preferred over afternoon/evening dosing 3

• Duration:

  • Continue treatment for 3 months after hemoglobin normalizes to replenish iron stores 2, 1
  • Hemoglobin should rise by approximately 2 g/dL after 3-4 weeks of treatment 2

• Enhancing Absorption:

  • Add ascorbic acid (vitamin C) when response is poor 2, 3
  • Take iron supplements with foods rich in vitamin C 1
  • Avoid taking with tea, coffee, calcium supplements, or antacids

When to Consider Parenteral Iron Therapy

Intravenous iron (such as ferric carboxymaltose) should be used when:

• Intolerance to at least two oral preparations 2
• Non-compliance with oral therapy 2
• Clinically active inflammatory bowel disease 1, 4
• Hemoglobin below 10 g/dL requiring rapid correction 1
• Patients needing erythropoiesis-stimulating agents 1
• Dialysis-dependent renal insufficiency 4
• Heart failure 4

IV Iron Dosing (Ferric Carboxymaltose)

For patients weighing ≥50 kg:

• 750 mg IV in two doses separated by at least 7 days (total 1,500 mg) 5
• Alternative: 15 mg/kg up to 1,000 mg as a single dose 5

For patients weighing <50 kg:

• 15 mg/kg IV in two doses separated by at least 7 days 5

Monitoring Response to Treatment

• Check hemoglobin after 2-4 weeks of therapy 1
• Continue monitoring every 4 weeks until hemoglobin normalizes 1
• Failure to respond (hemoglobin not rising by 2 g/dL after 3-4 weeks) may be due to:
  • Poor compliance
  • Misdiagnosis
  • Continued blood loss
  • Malabsorption 2

Special Considerations

Age-Based Investigation

• Patients >45 years with iron deficiency anemia should undergo both upper and lower GI investigations 2
• Patients <45 years with upper GI symptoms should have endoscopy and small bowel biopsy 2
• Patients <45 years without GI symptoms should have antiendomysial antibody testing to exclude celiac disease 2

Common Pitfalls to Avoid

1. Premature discontinuation of iron supplementation before iron stores are replenished 1
2. Inadequate monitoring of response to therapy 1
3. Accepting upper GI findings as the sole cause without lower GI evaluation (dual pathology occurs in 10-15% of patients) 1
4. Overlooking occult GI blood loss in men and postmenopausal women 1
5. Using inappropriate ferritin cutoffs for diagnosis 1
6. Failing to consider alternate-day dosing which may improve absorption and reduce side effects 3

Dietary Recommendations

Recommend foods rich in iron:

• Red meat, fish, and poultry
• Dark green leafy vegetables
• Iron-fortified cereals and breads
• Foods rich in vitamin C to enhance iron absorption 1

By following this structured approach to iron deficiency anemia management, clinicians can effectively treat patients while minimizing side effects and ensuring adequate replenishment of iron stores.