What is the treatment plan for a patient with iron deficiency anemia?

Treatment Plan for Iron Deficiency Anemia

Immediate Iron Replacement Therapy

Start oral ferrous sulfate 200 mg once daily, which is the preferred first-line treatment due to its effectiveness, low cost, and superior tolerability compared to multiple daily dosing. 1

• Add vitamin C (ascorbic acid) 250-500 mg with each iron dose to enhance absorption, particularly critical given your severely low iron saturation of 10% and ferritin of 7 ng/mL 2, 1
• Take iron on an empty stomach for optimal absorption, though taking with food is acceptable if gastrointestinal side effects occur 1
• If ferrous sulfate is not tolerated, switch to alternative formulations such as ferrous gluconate or ferrous fumarate, which are equally effective 2, 1
• Continue oral iron for 3 months after hemoglobin normalizes to fully replenish iron stores 2, 1

Expected Response and Monitoring Timeline

• Hemoglobin should rise by approximately 2 g/dL after 3-4 weeks of treatment 2, 1
• If no response occurs within 4 weeks, assess for non-adherence, ongoing blood loss, or malabsorption 1
• Monitor hemoglobin and red cell indices every 3 months for the first year, then again after another year 2, 1
• Recheck ferritin after 3 months of therapy to confirm store repletion 1

Investigation of Underlying Cause

You must identify and treat the underlying cause of iron deficiency while supplementing iron. 1

For Premenopausal Women (if applicable):

• Assess menstrual blood loss first, as menorrhagia accounts for iron deficiency in 5-10% of menstruating women 2, 1
• Consider pictorial blood loss assessment charts (80% sensitivity and specificity for detecting menorrhagia) 2, 1

For All Patients:

• Screen for celiac disease with antiendomysial antibody and IgA measurement, as this is a common cause of malabsorption 1, 3
• Perform bidirectional endoscopy (gastroscopy and colonoscopy) if you are male, postmenopausal female, or have alarm symptoms (weight loss, abdominal pain, family history of GI cancer) 2, 3
• Test for H. pylori at initial gastroscopy if performed 2

When to Switch to Intravenous Iron

Consider IV iron if oral therapy fails or specific conditions exist: 1

• Intolerance to at least two different oral iron preparations 2, 1
• Inadequate response to oral iron after 4 weeks of appropriate therapy 1
• Active inflammatory bowel disease with hemoglobin <10 g/dL 1
• Post-bariatric surgery (anatomic disruption of duodenal absorption) 1
• Celiac disease with inadequate response despite gluten-free diet adherence 1
• Ongoing gastrointestinal blood loss exceeding oral replacement capacity 1

IV Iron Formulation Preferences:

• Ferric carboxymaltose (500-1000 mg single doses, delivered within 15 minutes) is preferred for convenience and safety 2, 1
• Iron sucrose (200 mg over 10 minutes) is an alternative 2
• Avoid iron dextran due to higher anaphylaxis risk (0.6-0.7%) 2, 1
• All IV iron must be administered in medical facilities with resuscitation equipment available 2

Critical Pitfalls to Avoid

• Do not prescribe multiple daily doses (e.g., three times daily) - once-daily dosing improves tolerability with similar efficacy 1
• Do not stop iron when hemoglobin normalizes - continue for 3 months to replenish stores 2, 1
• Do not overlook vitamin C supplementation when oral iron response is suboptimal 2, 1
• Do not continue oral iron indefinitely without response - reassess after 4 weeks and switch to IV iron if hemoglobin fails to rise 1
• Do not fail to identify the underlying cause - iron supplementation alone is insufficient if ongoing blood loss continues 1

Failure to Respond

If anemia does not resolve within 6 months despite appropriate therapy: 1

• Reassess for ongoing blood loss 1
• Evaluate for malabsorption syndromes (celiac disease, atrophic gastritis, inflammatory bowel disease) 3
• Consider further gastrointestinal investigation with capsule endoscopy or CT/MRI enterography if red flags present 3
• Verify patient adherence to therapy 1
• Consider hematology consultation for complex cases 1