What is the first line treatment for iron deficiency anemia?

First-Line Treatment for Iron Deficiency Anemia

Oral iron supplementation should be considered as first-line treatment for iron deficiency anemia in patients with mild anemia, whose disease is clinically inactive, and who have not been previously intolerant to oral iron. 1

Diagnosis of Iron Deficiency Anemia

Iron deficiency anemia is diagnosed by:

• Low hemoglobin levels
• Low serum ferritin (<30 μg/L in patients without inflammation)
• In the presence of inflammation, serum ferritin up to 100 μg/L may still be consistent with iron deficiency
• Transferrin saturation <20%

Treatment Algorithm

First-Line Therapy: Oral Iron

1. Standard Dosing:

   • Ferrous sulfate 200 mg (containing approximately 65 mg elemental iron) once daily in the morning on an empty stomach 2
   • Alternative: Ferrous sulfate 200 mg three times daily if more rapid correction is needed 1

2. Optimization Strategies:

   • Take with vitamin C (ascorbic acid) to enhance absorption 2
   • Morning dosing is preferred over divided doses 2
   • Alternate-day dosing may improve absorption and reduce side effects 3

3. Alternative Oral Formulations (if ferrous sulfate is not tolerated):

   • Ferrous gluconate
   • Ferrous fumarate
   • Iron protein succinylate (may have better tolerability) 4
   • Liquid preparations if tablets are not tolerated 2

Monitoring Response

• Hemoglobin should increase by approximately 2 g/dL after 3-4 weeks of therapy 2
• A hemoglobin increase of <1.0 g/dL at day 14 strongly predicts treatment failure and need to switch to IV iron 5
• Continue iron supplementation for 3 months after correction of anemia to replenish iron stores 2
• Monitor hemoglobin concentration and red cell indices at three-monthly intervals for one year 2

When to Use Intravenous Iron (Second-Line)

Intravenous iron should be used as first-line treatment in:

1. Patients with clinically active inflammatory bowel disease 1
2. Patients with previous intolerance to oral iron 1
3. Patients with hemoglobin below 100 g/L 1
4. Patients who need erythropoiesis-stimulating agents 1
5. Patients with conditions affecting iron absorption (celiac disease, post-bariatric surgery) 1, 6
6. Patients who fail to respond to oral iron therapy 1, 2

Special Considerations

• Inflammatory Bowel Disease: Determine whether anemia is due to inadequate intake/absorption or blood loss; treat active inflammation to enhance iron absorption 1
• Portal Hypertensive Gastropathy: Start with oral iron; switch to IV if ongoing bleeding with poor response 1
• Celiac Disease: Ensure adherence to gluten-free diet to improve iron absorption 1

Common Pitfalls to Avoid

1. Failure to investigate underlying cause of iron deficiency anemia, potentially missing serious pathology like gastrointestinal malignancy 2
2. Inadequate duration of treatment, leading to insufficient replenishment of iron stores 2
3. Missing malabsorption conditions that impair iron absorption 2
4. Using divided doses of oral iron, which may increase hepcidin and reduce absorption 3
5. Continuing oral iron despite poor response at 2 weeks 5

Treatment Goals

• Restore hemoglobin levels and MCV to normal
• Replenish body iron stores
• Identify and treat the underlying cause
• Resolution of anemia should be achieved by six months in 80% of patients 2

Following this algorithm will ensure optimal management of iron deficiency anemia with appropriate selection of first-line therapy based on patient characteristics and disease status.