How to manage iron deficiency anemia with low iron, high Total Iron-Binding Capacity (TIBC), and low hemoglobin in a patient not on iron supplementation?

Management of Iron Deficiency Anemia with Severe Iron Depletion

Start oral ferrous sulfate 200 mg once daily immediately, taken in the morning on an empty stomach with 500 mg vitamin C, and continue for 3 months after hemoglobin normalizes to replenish iron stores. 1

Immediate Treatment Approach

Your laboratory values reveal severe iron deficiency anemia requiring urgent treatment:

• Hemoglobin 9.7 g/dL (moderate anemia)
• Iron saturation 8.49% (severely depleted, normal >20%)
• Serum iron 19 (critically low)
• TIBC 225 (elevated, indicating iron deficiency)
• Ferritin 124 (appears normal but may mask true deficiency if inflammation present) 2

Oral Iron Supplementation Protocol

• Take ferrous sulfate 200 mg once daily in the morning - this single daily dose is superior to multiple daily doses, improving tolerability while maintaining effectiveness 1
• Add vitamin C (ascorbic acid) 500 mg with each iron dose - this is particularly critical given your severely low transferrin saturation of 8.49%, as vitamin C significantly enhances iron absorption 2, 1
• Take on an empty stomach for optimal absorption, though taking with food is acceptable if gastrointestinal side effects occur 1
• Alternative formulations (ferrous gluconate or ferrous fumarate) are equally effective if ferrous sulfate causes intolerable side effects 2, 1

Expected Response Timeline

• Hemoglobin should rise by approximately 2 g/dL after 3-4 weeks of treatment 2, 1
• Continue iron therapy for 3 months after hemoglobin normalizes to fully replenish iron stores - this is critical and commonly overlooked 2, 1
• Monitor hemoglobin and red cell indices at 4 weeks to assess response 1

When to Switch to Intravenous Iron

Consider IV iron if you meet any of these criteria:

• Intolerance to at least two different oral iron preparations 2, 1
• No hemoglobin rise of 2 g/dL after 4 weeks of oral therapy 2, 1
• Conditions affecting iron absorption (inflammatory bowel disease with active inflammation, celiac disease with ongoing gluten exposure, post-bariatric surgery) 2, 1
• Hemoglobin remains below 10 g/dL with active inflammatory bowel disease 2

Preferred IV iron formulations include ferric carboxymaltose (500-1000 mg single doses, delivered within 15 minutes) which can replace iron deficits with 1-2 infusions 1

Investigation of Underlying Cause

You must identify and treat the source of iron loss while supplementing iron - this is essential for long-term management 2, 1

For Premenopausal Women:

• Assess menstrual blood loss first - menorrhagia, pregnancy, and breastfeeding account for iron deficiency in 5-10% of menstruating women 2, 1
• Screen for celiac disease with antiendomysial antibody and IgA measurement - this is a common cause of malabsorption 2, 1
• Gastrointestinal endoscopy only if you have upper GI symptoms, are over age 45, or have alarm symptoms (rectal bleeding, family history of colon cancer) 2, 1

For Men and Postmenopausal Women:

• Upper and lower GI investigations are mandatory unless there is obvious non-GI blood loss 2
• Both upper endoscopy and colonoscopy should be performed to exclude malignancy 2

Monitoring Protocol

• Recheck hemoglobin at 4 weeks - failure to rise by 2 g/dL indicates poor compliance, continued blood loss, or malabsorption 2, 1
• Monitor every 3 months for the first year, then again after another year 2, 1
• Provide additional iron supplementation if hemoglobin or MCV falls below normal during follow-up 2

Critical Pitfalls to Avoid

• Do not stop iron therapy when hemoglobin normalizes - you must continue for 3 months to replenish stores 2, 1
• Do not use multiple daily doses - once-daily dosing is better tolerated with similar efficacy 1, 3
• Do not overlook vitamin C supplementation - this significantly enhances absorption, especially critical with your iron saturation of 8.49% 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 without addressing the source of loss 2, 1

Failure to Respond

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

• Reassess for ongoing blood loss 1
• Evaluate for malabsorption syndromes (celiac disease, inflammatory bowel disease, H. pylori infection) 2, 1
• Verify patient adherence to therapy 2, 1
• Consider hematology consultation for complex cases 1

Special Consideration: Ferritin Interpretation

Your ferritin of 124 ng/mL appears normal but may mask true iron deficiency if inflammation is present 2. In the presence of inflammation, ferritin up to 100 ng/mL can still indicate iron deficiency, and values between 30-100 ng/mL suggest combined iron deficiency and anemia of chronic disease 2. Your severely low iron saturation (8.49%) and elevated TIBC (225) confirm true iron deficiency despite the ferritin level 2.