🩸 Oral iron supplements can be tricky to compare. While efficacy and tolerability are similar at equal doses of elemental iron, the percentage of elemental iron varies between products. Here's the breakdown..
- Start with 100-200 mg/day elemental iron for iron deficiency. Common options:
- Ferrous sulfate/fumarate: 65-100 mg elemental iron/tab
- Ferrous gluconate: ~35 mg elemental iron/tab
More elemental iron can mean more GI upset (e.g., constipation). Start with one tab daily, titrating to BID or TID over 1-2 weeks.
🧠 Pro tip: Iron is best absorbed on an empty stomach but okay to take with food if needed for GI comfort.
- To reduce GI upset..
- Lower the dose or use once daily dosing. But remember, it may take longer to correct the deficiency.
Don’t rely on stool softeners (e.g., Docusate) for constipation. Try Vitamin C (200 mg or 8 oz OJ) to boost iron absorption by about 10%.
⚠️ Watch out for..
- Slow-release or enteric-coated products—these may not absorb as well.
- No proven benefit for polysaccharide-iron complex, carbonyl iron, or heme iron polypeptide.
- 📊 Monitor hemoglobin monthly in iron-deficient patients to track progress.
References
- Camaschella C. Iron-deficiency anemia. N Engl J Med. 2015;372(19):1832-1843.
- Dull RB, Davis E. Heme iron polypeptide for the management of anaemia of chronic kidney disease. J Clin Pharm Ther. 2015;40(4):386-390.
- Liu TC, Lin SF, Chang CS, Yang WC, Chen TP. Comparison of a combination ferrous fumarate product and a polysaccharide iron complex as oral treatments of iron deficiency anemia: a Taiwanese study. Int J Hematol. 2004;80(5):416-420.
