What is the treatment for iron deficiency?

Treatment of Iron Deficiency

Oral iron supplementation is the first-line treatment for iron deficiency, with ferrous sulfate 200 mg (providing 65 mg elemental iron) once daily being the preferred formulation due to its low cost and effectiveness. 1

Diagnosis and Initial Assessment

• Iron deficiency is diagnosed by:
  • Low serum ferritin (<30 ng/mL) in individuals without inflammation
  • Transferrin saturation <20%
  • Clinical symptoms may include fatigue, irritability, depression, difficulty concentrating, restless legs syndrome, pica, dyspnea, and exercise intolerance 2

Treatment Algorithm

First-Line Treatment: Oral Iron

• Dosing recommendations:

  • Adults: 50-100 mg elemental iron daily (equivalent to 200 mg ferrous sulfate once daily) 1
  • Consider alternate-day dosing if daily dosing causes side effects 1
  • Continue treatment for 3 months after normalization of iron parameters to ensure replenishment of iron stores 1

• Optimization strategies:

  • Take with vitamin C (orange juice or vitamin C supplement) to enhance absorption 1
  • Avoid taking with tea, coffee, calcium, or antacids which inhibit absorption
  • Take on an empty stomach if tolerated

• Monitoring:

  • Hemoglobin should rise by approximately 2 g/dL after 3-4 weeks 3
  • Monitor complete blood count and iron studies every 3 months for one year, then after another year 1
  • If no response after 4 weeks despite compliance, consider further evaluation 3

Second-Line Treatment: Intravenous Iron

Intravenous iron should be used when:

1. Patient has intolerance to at least two oral preparations 3
2. Poor response to oral therapy
3. Active inflammation is present
4. Hemoglobin is below 10 g/dL
5. Patient has malabsorption (e.g., celiac disease, post-bariatric surgery)
6. Ongoing blood loss exceeds intestinal absorption capacity 1, 4

• IV iron formulations:
  • Prefer formulations that can replace iron deficits with 1-2 infusions 1
  • Ferric carboxymaltose allows rapid administration of large single doses (1000-2000 mg) 3
  • Iron sucrose (Venofer) is administered in smaller doses (100-200 mg) per session 5

Special Populations

Chronic Heart Failure

• IV ferric carboxymaltose is recommended for iron deficiency in chronic heart failure (class of recommendation IIa, level of evidence A) 3
• Benefits include improved exercise capacity, quality of life, and potentially reduced hospitalizations 3

Chronic Kidney Disease

• For hemodialysis-dependent CKD: IV iron (iron sucrose or ferric gluconate) is indicated 5, 6
• Dosing depends on specific formulation and patient characteristics 5

Pregnant Women

• Higher iron requirements (27 mg daily)
• IV iron may be indicated during second and third trimesters 1

Inflammatory Conditions

• IV iron is preferred in patients with inflammatory bowel disease and other chronic inflammatory conditions 1
• Oral iron may be poorly absorbed and can exacerbate gastrointestinal symptoms in IBD

Common Pitfalls to Avoid

• Inadequate duration of treatment (should continue for 3 months after normalization)
• Failure to add vitamin C to enhance absorption
• Administering oral iron with inhibitors of absorption (tea, coffee, calcium)
• Stopping treatment too early when hemoglobin normalizes but before iron stores are replenished
• Overlooking the underlying cause of iron deficiency, particularly in men and postmenopausal women where gastrointestinal blood loss should be investigated 3, 7

Dietary Recommendations

• Include heme iron sources (meat, poultry, fish) which have higher bioavailability
• Pair non-heme iron sources with vitamin C-rich foods to enhance absorption
• Plant-based diets require approximately 1.8 times more dietary iron due to lower bioavailability 1

Iron deficiency treatment should be tailored based on severity, underlying cause, and patient characteristics, with oral iron being appropriate for most patients and IV iron reserved for specific indications.