What is the appropriate treatment for a patient with laboratory-confirmed iron deficiency anemia?

Treatment for Laboratory-Confirmed Iron Deficiency Anemia

All patients with iron deficiency anemia should receive oral iron supplementation with ferrous sulfate 200 mg three times daily (or one tablet daily if not tolerated) to correct anemia and replenish body stores, and treatment should continue for three months after hemoglobin normalization. 1

Laboratory Interpretation

Your labs confirm iron deficiency anemia:

• Low hemoglobin (11.6 g/dL) and low hematocrit (34.4%) indicate anemia 2
• Low MCV (77 fL) and low MCH (26 pg) indicate microcytic anemia 1
• Iron saturation of 27% is borderline but combined with microcytosis strongly suggests iron deficiency 2
• The pattern is consistent with iron deficiency anemia requiring treatment 1

First-Line Treatment: Oral Iron Supplementation

Recommended regimen:

• Ferrous sulfate 200 mg three times daily is the most cost-effective first-line therapy 1
• Alternative equally effective options include ferrous gluconate or ferrous fumarate if ferrous sulfate is not tolerated 1
• If gastrointestinal side effects occur, reduce to one tablet daily or every other day 1, 2
• Liquid preparations may be better tolerated when tablets cause problems 1

Adjunctive measures:

• Ascorbic acid (vitamin C) enhances iron absorption and should be considered if response is poor 1

Expected Response and Monitoring

Timeline for improvement:

• Hemoglobin should rise by 2 g/dL after 3-4 weeks of treatment 1
• Monitor hemoglobin response within the first 4 weeks 1
• Continue treatment for 3 months after hemoglobin normalizes to replenish iron stores 1

Failure to respond indicates:

• Poor compliance (most common) 1
• Continued blood loss 1
• Malabsorption 1
• Misdiagnosis 1

When to Use Intravenous Iron

Parenteral iron is indicated only when:

• Intolerance to at least two different oral iron preparations 1
• Documented malabsorption (celiac disease, post-bariatric surgery, inflammatory bowel disease) 2, 3
• Chronic inflammatory conditions (chronic kidney disease, heart failure, cancer) 2
• Ongoing significant blood loss 2
• Non-compliance with oral therapy 1

Important caveat: Intravenous iron is more expensive, carries risk of anaphylaxis, and provides no faster hemoglobin rise than oral preparations 1

Long-Term Follow-Up

Monitoring schedule after normalization:

• Check hemoglobin and MCV every 3 months for one year, then again at 2 years 1
• Restart oral iron if hemoglobin or MCV falls below normal 1
• Check ferritin if values are borderline 1

Investigation for Underlying Cause

The cause of iron deficiency must be identified and treated to prevent recurrence 1, 2:

For men and postmenopausal women:

• Gastroscopy and colonoscopy should be performed to exclude gastrointestinal malignancy or bleeding source 1, 2
• This is critical as gastrointestinal cancer is a common cause in this population 3, 4

For premenopausal women:

• Menstrual blood loss, pregnancy, and breastfeeding are the most common causes 1
• Women under age 45 without gastrointestinal symptoms may not require endoscopy initially 1
• Women over age 45 should undergo full gastrointestinal investigation 1

Additional testing to consider:

• Celiac disease screening (tissue transglutaminase antibody with IgA level) 3
• Assessment for NSAID use, which commonly causes occult GI bleeding 2
• Exclude hematuria if urinary symptoms present 1

Common Pitfalls to Avoid

• Do not defer iron replacement while awaiting investigations unless colonoscopy is imminent 1
• Do not use faecal occult blood testing as it is insensitive and non-specific 1
• Do not routinely check liver function, renal function, or clotting studies unless history suggests systemic disease 1
• Do not stop treatment when hemoglobin normalizes—continue for 3 months to replenish stores 1
• Do not assume dietary deficiency alone without investigating for pathological causes, especially in men and postmenopausal women 2, 3