Treatment of Iron Deficiency Anemia

Initial Treatment Approach

The American Gastroenterological Association recommends starting oral ferrous sulfate 200 mg once or twice daily as the most cost-effective first-line treatment to correct severe iron deficiency 1, 2
Iron saturation of 9% is considered severely low, with normal being greater than 20% 3
High TIBC and low iron indicate true iron deficiency 1, 2

The recommended regimen is ferrous sulfate 200 mg once daily or twice daily, providing 65 mg elemental iron per dose 1, 2, 4
Alternative preparations include ferrous fumarate or ferrous gluconate, which are equally effective 1, 2, 5
Continue oral iron for 3 months after hemoglobin normalizes to replenish iron stores 2, 5, 6
Recent data shows 60 mg elemental iron twice daily produces faster hemoglobin rise than alternate-day dosing 4
If gastrointestinal side effects occur, switch to alternate-day dosing rather than discontinuing treatment 4
Lower doses (50-100 mg elemental iron daily) may be better tolerated with reasonable efficacy 4
Consider adding ascorbic acid (vitamin C) 250-500 mg with iron doses to enhance absorption 1, 2, 7

Hemoglobin should rise by at least 10 g/L (1 g/dL) after 2 weeks of daily oral therapy 4
Hemoglobin increase of 2 g/dL after 3-4 weeks is expected 1, 2
Failure to achieve this response indicates non-compliance, malabsorption, continued bleeding, or other pathology 1, 2, 4
Recheck hemoglobin and iron studies at 2 weeks to confirm response 4
Repeat testing at 8-10 weeks to assess treatment success 3

Consider IV iron if there is intolerance to at least two different oral iron preparations 1, 2, 7
Failure to respond to oral iron after 2 weeks (no hemoglobin rise ≥10 g/L) is an indication for IV iron 4
Malabsorption conditions, such as celiac disease or inflammatory bowel disease, may require IV iron 3, 7
Severe symptomatic anemia requiring rapid correction may be treated with IV iron 4, 7

Transfusion is rarely indicated for iron deficiency anemia because most patients adapt to slowly developing anemia 4
Reserve transfusion only for severe symptomatic anemia with circulatory compromise 4
If transfused, target hemoglobin 70-90 g/L (80-100 g/L with unstable coronary disease), then follow with iron replacement 4

Identify and treat the source of iron loss, especially in adults 1, 2
Age >45 years: Upper endoscopy with small bowel biopsy AND colonoscopy (or barium enema) to exclude gastrointestinal bleeding or malignancy 1, 2, 8
Age <45 years: Consider celiac disease screening (anti-endomysial antibodies with IgA level), endoscopy only if upper GI symptoms present 1, 2
Menstruating women: Heavy menstrual bleeding is a common cause, but still investigate if symptoms persist or age >45 years 1, 2, 8

Don't stop oral iron too early: Continue for 3 months after hemoglobin normalizes to replenish stores 2, 5, 6
Don't use modified-release preparations: These are less suitable for prescribing due to reduced absorption 4
Don't assume dietary deficiency alone: Always investigate for pathological blood loss, especially in adults 1, 2
Don't use parenteral iron as first-line unless specific contraindications to oral therapy exist 1, 2, 7
Don't supplement iron if ferritin is normal or high: This is potentially harmful and not recommended 3