Treatment for Chronic Iron Deficiency Anemia
The treatment for chronic iron deficiency anemia should include oral ferrous sulfate 200 mg of elemental iron daily in 2-3 divided doses, or as a single daily dose of 200 mg ferrous sulfate (providing 65 mg elemental iron) with vitamin C (250-500 mg) to enhance absorption, continued for 3 months after hemoglobin normalization to replenish iron stores. 1
Diagnosis Confirmation
Before initiating treatment, confirm iron deficiency anemia with:
- Hemoglobin <11.5 g/dL
- Serum ferritin typically <30 ng/mL (note: levels up to 100 μg/L may still indicate iron deficiency with inflammation)
- Transferrin saturation <20% 1, 2
Oral Iron Therapy: First-Line Treatment
Formulations and Dosing
Ferrous sulfate: Preferred formulation (65 mg elemental iron per 325 mg tablet) 1, 3
- Adult dosing: 200 mg elemental iron daily, divided into 2-3 doses
- Can also be given as a single daily dose with vitamin C
- Alternative: Consider alternate-day dosing which may improve absorption and reduce side effects 4
Alternative formulations (if ferrous sulfate not tolerated):
Administration Tips
- Take on an empty stomach (2 hours before or 1 hour after meals) for optimal absorption 1
- Add vitamin C (250-500 mg) to enhance iron absorption 1
- Morning administration is preferred (circadian hepcidin patterns affect absorption) 4
- Avoid taking with absorption inhibitors (tea, coffee, calcium, antacids) 1
Intravenous Iron Therapy: When to Consider
IV iron is indicated as first-line therapy for patients with:
- Active infection
- Hemoglobin below 10 g/dL
- Need for rapid correction of anemia
- Previous intolerance to oral iron
- Conditions with impaired absorption (celiac disease, post-bariatric surgery)
- Chronic inflammatory conditions (CKD, heart failure, IBD, cancer) 1, 2
IV Iron Dosing (based on weight and hemoglobin level)
| Hemoglobin g/dL | Body weight <70 kg | Body weight ≥70 kg |
|---|---|---|
| 10-12 [women] | 1000 mg | 1500 mg |
| 10-13 [men] | 1500 mg | 1500 mg |
| 7-10 | 1500 mg | 2000 mg |
IV Iron Formulations
- Ferric carboxymaltose (preferred): Up to 1000 mg in a single 15-minute infusion 1
- Iron sucrose: 200 mg over 10 minutes 1
- Iron dextran: 20 mg/kg over 6 hours (can also be given intramuscularly) 1
Monitoring and Follow-up
- Check hemoglobin after 2-4 weeks of treatment (expect increase of ~2 g/dL) 1
- Monitor hemoglobin and red cell indices every 3 months for 1 year, then after another year 1
- Target values:
- Hemoglobin >12 g/dL for women and >13 g/dL for men
- Ferritin >100 μg/L
- Transferrin saturation >20% 1
Special Populations
- Athletes and active women: May require higher daily iron intake (22 mg/day) 1
- Chronic kidney disease: IV iron should be considered if serum ferritin is >100 ng/mL 1
- Inflammatory bowel disease or post-bariatric surgery: IV iron is preferred 1
- Plant-based diets: Require approximately 1.8 times more dietary iron 1
- Pregnancy: IV iron indicated during second and third trimesters if needed 2
Common Pitfalls to Avoid
- Stopping treatment too early before iron stores are replenished 1
- Failing to add vitamin C to enhance absorption 1
- Administering oral iron with absorption inhibitors 1
- Using parenteral iron when oral therapy would be effective 1
- Inadequate dosing that underestimates total iron deficit 1
- Delaying investigation of underlying causes, especially in men and postmenopausal women 1, 2
- Gastrointestinal blood loss is the most common cause in men and postmenopausal women
- Menstrual blood loss and pregnancy are common causes in premenopausal women
Dietary Recommendations
- Increase intake of iron-rich foods:
- Heme iron: Red meat, poultry, fish (better absorbed)
- Non-heme iron: Leafy greens, legumes, fortified cereals
- Consume vitamin C-rich foods with meals to enhance absorption 1