What is the recommended treatment for iron deficiency anemia?

Iron Deficiency Anemia Treatment

The gold standard treatment for iron deficiency anemia is oral iron supplementation with 50-100 mg of elemental iron once daily, taken in the fasting state, with continuation for 3 months after hemoglobin normalization to replenish iron stores. 1

First-Line Treatment: Oral Iron Therapy

Dosing and Administration

• Recommended dosing: 60-120 mg elemental iron daily (equivalent to 324 mg ferrous sulfate which provides 65 mg of elemental iron) 1, 2
• Optimal timing: Take as a morning single dose on an empty stomach 1
• Absorption enhancement: Take with vitamin C (250-500 mg) to improve absorption 1
• Alternative dosing strategy: For improved tolerability and absorption, consider alternate-day dosing with 60-120 mg elemental iron 3

Monitoring Response

1. Check hemoglobin after 2-4 weeks of treatment initiation 1
2. A critical decision point is an increase in hemoglobin of at least 10 g/L (1 g/dL) after 2 weeks
   • This strongly predicts successful treatment (sensitivity 90.1%, specificity 79.3%) 4
3. Continue monitoring every 4 weeks until hemoglobin normalizes 1
4. After normalization, continue iron for 3 months to replenish stores 1
5. Long-term follow-up with iron studies every 3 months during maintenance phase 1

Second-Line Treatment: Intravenous Iron

Indications for IV Iron (First-Line)

Intravenous iron should be considered as first-line treatment in the following scenarios:

• Clinically active inflammatory bowel disease 5
• Previous intolerance to oral iron 5, 1
• Hemoglobin below 100 g/L (10 g/dL) 5
• No hemoglobin increase of at least 10 g/L after 2 weeks of oral therapy 1, 4
• Malabsorption conditions 1
• Chronic inflammatory conditions 1
• Ongoing blood loss exceeding oral replacement capacity 1

IV Iron Options

• Ferric carboxymaltose: Maximum single dose of 1000 mg, infused over 15 minutes 1
• Iron sucrose: 200 mg per injection over 10-30 minutes 1
• Iron dextran: Can replenish iron in a single infusion but carries risk of serious reactions (0.6-0.7%) 1

Maintenance and Follow-up

• Re-treatment should be initiated when serum ferritin drops below 100 μg/L or hemoglobin falls below gender-specific thresholds 5, 1
• Monitor hemoglobin every 3 months for 1 year, then after another year once hemoglobin normalizes 1
• Provide further oral iron if hemoglobin or red cell indices fall below normal 1

Identifying and Treating the Underlying Cause

This is essential for successful long-term management:

• Evaluate for gastrointestinal blood loss in men and postmenopausal women 1
• Assess for heavy menstrual bleeding in premenopausal women 1
• Screen for malabsorption conditions (e.g., celiac disease) 1
• Evaluate dietary intake patterns 1
• Consider testing for H. pylori 1

Common Pitfalls to Avoid

1. Inadequate monitoring: Failure to check hemoglobin response after 2 weeks may delay recognition of treatment failure 1
2. Premature discontinuation: Stopping iron supplementation once hemoglobin normalizes without continuing for 3 months to replenish iron stores 1
3. Ignoring non-response: Failure to respond to oral iron may indicate non-compliance, malabsorption, continued bleeding, or concurrent deficiencies 1
4. Using inappropriate ferritin cutoffs in patients with inflammation (ferritin is an acute phase reactant) 5, 1
5. Failing to identify the underlying cause of iron deficiency, particularly in men and postmenopausal women 1

Diagnostic Criteria

Iron deficiency can be diagnosed using:

• Serum 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

By following this structured approach to iron deficiency anemia treatment, monitoring response appropriately, and addressing the underlying cause, clinicians can effectively manage this common condition and improve patient outcomes.