Treatment of Iron Deficiency Anemia
For patients with iron deficiency anemia, oral ferrous sulfate 324 mg (65 mg elemental iron) once daily in the morning with vitamin C is the recommended first-line treatment. 1, 2
Diagnosis Confirmation
The patient's laboratory values clearly indicate iron deficiency anemia:
- Ferritin: 4 ng/mL (severely depleted)
- Serum Iron: 37 µg/dL (low)
- TIBC: 465 µg/dL (high)
- Transferrin Saturation: 8% (low, normal is 20-50%)
- Hemoglobin: 11.0 g/dL (low)
- MCV: 77.9 fL (microcytic)
- MCH and MCHC: both low
Treatment Algorithm
First-Line Treatment
- Oral iron supplementation: Ferrous sulfate 324 mg (65 mg elemental iron) once daily in the morning 1, 2
- Take with vitamin C (orange juice or vitamin C supplement) to enhance absorption 1
- Taking iron on alternate days may improve absorption and reduce gastrointestinal side effects if daily dosing is not tolerated 3
Monitoring Response
- Check hemoglobin after 3-4 weeks of treatment 1
- Expected response: approximately 2 g/dL increase in hemoglobin 1, 4
- A hemoglobin increase of at least 1.0 g/dL at day 14 predicts adequate response to oral iron therapy 1, 4
- If hemoglobin increase is <1.0 g/dL at day 14, consider switching to IV iron 4
- Recheck ferritin and hemoglobin in 3 months 1
- Target ferritin level: at least 100 μg/L 1
- Target hemoglobin: 11-13 g/dL 1
Indications for IV Iron
Consider IV iron if any of the following are present:
- Poor response to oral iron (hemoglobin increase <1.0 g/dL after 14 days) 4
- Intolerance to oral iron 5
- Malabsorption conditions 5
- Ongoing blood loss at a rate too rapid for oral iron to compensate 1
- Chronic inflammatory conditions 5
Addressing the Underlying Cause
Identifying and treating the underlying cause of iron deficiency is essential. Common causes include:
- Menstrual blood loss in premenopausal women 5, 6
- Gastrointestinal blood loss (especially important to investigate in men and postmenopausal women) 5, 6
- Malabsorption (celiac disease, post-bariatric surgery) 5
- Inadequate dietary intake 5
- Pregnancy 5
Common Pitfalls to Avoid
- Inadequate follow-up: Ensure proper monitoring of hemoglobin and ferritin levels 1
- Premature discontinuation: Continue iron supplementation until iron stores are replenished (ferritin >100 μg/L) 1
- Overlooking the underlying cause: Always investigate the reason for iron deficiency 1, 6
- Inappropriate parenteral iron use: Reserve for specific indications 1
- Missing concomitant conditions: Consider other causes of anemia if response is inadequate 1
- Excessive iron supplementation: Can cause iron overload and should be avoided 6
Side Effects Management
If gastrointestinal side effects occur:
- Consider alternate-day dosing 3
- Take with food if necessary (though this may reduce absorption)
- Consider different iron formulations if intolerance persists 7
The American Gastroenterological Association guidelines provide clear direction for iron deficiency anemia treatment, with oral ferrous sulfate as the first-line therapy and specific criteria for when to transition to IV iron based on treatment response.