1IV Iron Formulations — Comparative Guide (India)
| Formulation | Standard Infusion Dose | Max Single Dose | Clinical Administration Notes |
|---|---|---|---|
| Iron Sucrose (Venofer / Feronia) | 100–200 mg in 100 mL NS over 15–30 min | 200 mg | Safest profile in hemodialysis; low anaphylaxis risk; no test dose required. Repeated sessions needed for large deficits. |
| Ferric Carboxymaltose (Injectafer / Encicarb) | 500–1000 mg in 250 mL NS over 15 min | 1000 mg (or 20 mg/kg) | Rapidly corrects large deficits in 1–2 visits; preferred in 2nd/3rd trimester pregnancy; monitor serum phosphate. |
| Iron Dextran (Imferon) | Total Dose Infusion (TDI) over 4–6 hrs | Total deficit | MANDATORY 25 mg IV test dose with 60-min observation due to higher risk of dextran-mediated anaphylaxis. |
2The Ganzoni Equation — Mechanics & Physics
First described by A.M. Ganzoni in 1970, the formula calculates the exact quantity of elemental iron required to restore the circulating hemoglobin mass and replenish depot iron stores:
Derivation of the 2.4 Factor: The factor originates from blood volume (~7% or 0.07 L/kg of body weight) multiplied by the iron content of hemoglobin (0.34% or 3.4 mg of iron per gram of Hb). Converting units: 0.07 × 3.4 × 10 (conversion factor from g/dL to g/L) = 2.38, rounded to 2.4 for rapid clinical calculation.
Iron Stores Component
For most non-pregnant adults weighing more than 35 kg, an iron-stores value of 500 mg is used as a standard depot replacement figure, broadly approximating a total body iron store sufficient to avoid early recurrence of deficiency. For children and adults under 35 kg, 15 mg/kg of body weight is used instead. In pregnancy, many obstetric protocols set the stores component to zero or a much lower value, since the immediate clinical priority is correcting the haemoglobin deficit before delivery rather than fully repleting long-term stores — this also keeps the calculated total dose, and therefore the number of infusions, lower and more practical within the time available in pregnancy.
Worked Example
A 60 kg non-pregnant woman with Hb 7.5 g/dL and a target Hb of 12 g/dL: Iron deficit (body) = 60 × (12 − 7.5) × 2.4 = 648 mg. Adding standard stores of 500 mg gives a total iron deficit of 1148 mg. At 200 mg per session, this would require roughly six sessions of iron sucrose, or it could potentially be corrected in a single 1000 mg ferric carboxymaltose infusion plus a small top-up, illustrating why product choice materially affects the number of visits needed for the same calculated deficit.
3Iron Deficit in Pregnancy (FOGSI & Anaemia Mukt Bharat)
Per the National Family Health Survey (NFHS-5), over 50% of pregnant Indian women are anaemic. In pregnancy, two specific modifications to the Ganzoni formula apply:
- Trimester-Specific Target Hb: WHO guidelines recommend a target Hb of 11.0 g/dL in the 1st and 3rd trimesters, lowered to 10.5 g/dL in the 2nd trimester due to physiological hydraemia (plasma volume expansion exceeding red cell mass).
- Omission of Iron Stores (Stores = 0 mg): The primary obstetric imperative is elevating maternal hemoglobin to safe margins prior to delivery rather than fully filling long-term reticuloendothelial ferritin reserves. Setting stores to zero avoids unnecessary additional infusions.
4Chronic Kidney Disease & Dialysis Targets
In CKD (particularly stage 5D on hemodialysis), systemic inflammation elevates circulating hepcidin, blocking enterocyte ferroportin channels and completely preventing oral iron absorption. Parenteral administration bypasses hepcidin.
Per KDIGO 2012 guidelines, target hemoglobin in CKD is deliberately conservative: 10.0 to 11.5 g/dL. Normalizing hemoglobin above 12–13 g/dL with erythropoiesis-stimulating agents (ESAs) and iron increases stroke, vascular access thrombosis, and cardiovascular mortality (CHOIR and CREATE trials).
5Safety, Hypophosphataemia & Precautions
- Hypersensitivity & Fishbane Reactions: Labile free iron can trigger self-limiting flushing and arthralgias (Fishbane reactions), which resolve without epinephrine. However, genuine anaphylaxis can occur; resuscitative equipment must be on hand with 30-minute post-infusion observation.
- FCM-Induced Hypophosphataemia: Ferric carboxymaltose stimulates intact FGF-23, inducing severe renal phosphate wasting. Screen serum phosphate prior to repeated high-dose FCM cycles.
- Contraindication in Active Sepsis: Avoid parenteral iron during active systemic bacteremia, as circulating iron acts as an essential growth substrate for pathogens.
6Frequently Asked Questions
How to calculate iron deficit?+
Why are iron stores omitted in pregnancy?+
Why is iron sucrose capped at 200 mg per infusion?+
How is iron deficit calculated in CKD or dialysis patients?+
Is oral iron preferred over IV iron in pregnancy?+
Related Calculators
7Clinical References
- Ganzoni AM. Eisen-Dextran intravenös: ein therapeutischer und experimenteller Beitrag. Schweiz Med Wochenschr. 1970;100(7):301–303.
- World Health Organization. WHO recommendations on antenatal care for a positive pregnancy experience. Geneva: WHO; 2016.
- Kidney Disease: Improving Global Outcomes (KDIGO) Anemia Work Group. KDIGO Clinical Practice Guideline for Anemia in Chronic Kidney Disease. Kidney Int Suppl. 2012;2(4):279–335.
- Federation of Obstetric and Gynaecological Societies of India (FOGSI). Good Clinical Practice Recommendations on Iron Deficiency Anaemia in Pregnancy. 2021.
- Ministry of Health and Family Welfare (MoHFW), Government of India. Anaemia Mukt Bharat: Operational Guidelines for Intensified National Iron Plus Initiative. 2018.
- Auerbach M, Macdougall I. The available intravenous iron formulations: history, efficacy, and toxicology. Hemodial Int. 2017;21(Suppl 1):S83–S92.
- National Family Health Survey (NFHS-5), India, 2019-21: State and National Factsheets. International Institute for Population Sciences (IIPS).
- Manufacturer Prescribing Information: Iron Sucrose (Venofer), Ferric Carboxymaltose (Injectafer), Iron Dextran (Imferon).