Ferric Carboxymaltose (FCM) Dose Calculator

Estimate the total intravenous iron requirement using the Ganzoni formula, with pregnancy-specific checks based on the Government of India operational guidance for IV iron treatment in pregnant women and lactating mothers.

✓ Ganzoni formula ✓ Pregnancy & lactation modes ✓ Safety screening ✓ 50 mg/mL FCM volume aid

Calculate FCM requirement

Enter clinically verified values. The calculator does not send the entered calculator data to the server.

Pregnant Lactating / postpartum

Body weight * Use pre-pregnancy weight. If unavailable, use weight recorded at the first first-trimester visit, as specified by the NHM guideline.

Actual Hb * Use a recent, clinically reliable haemoglobin result.

Gestational age For pregnancy mode. NHM IV iron indications begin after 13 weeks for moderate anaemia.

Target Hb * Pregnancy default: 11.0 g/dL, matching Annexure III of the NHM guideline.

Serum ferritin Optional. NHM guidance lists ferritin >150 µg/L as a contraindication to injectable iron.

Safety screening

Known/suspected thalassemia, sickle-cell disease or haemolytic anaemia Anaemia is known to be due to a cause other than iron deficiency Jaundice or cirrhosis / significant liver disorder Acute cardiac failure Previous hypersensitivity to injectable iron / FCM preparation Fever or acute infection / acute illness

Estimated total iron requirement

Calculated with the entered weight, actual Hb and target Hb.

— mg elemental iron

Hb deficit

—

FCM volume at 50 mg/mL

—

Maximum single dose

1,000 mg

Guideline reference

Key points used by this calculator.

Ganzoni formulaTotal iron deficit = 2.4 × body weight (kg) × (target Hb − actual Hb) + iron-store allowance.

Pregnancy target Hb11.0 g/dL in Annexure III of the Government of India guideline.

Iron-store allowance500 mg when pregnant weight is >35 kg; 15 mg/kg when weight is <35 kg.

FCM concentrationThe guideline describes FCM at 50 mg elemental iron/mL.

Single sitting limitThe guideline states a maximum FCM dose of 1,000 mg in one session.

Pregnancy-period limitThe NHM guideline states that FCM should not exceed 1,500 mg in one pregnancy period.

Formula

Total iron deficit (mg) = 2.4 × weight (kg) × [target Hb − actual Hb] + iron-store allowance

Clinical context

The Government of India guideline identifies IV iron for selected pregnant and lactating women with iron-deficiency anaemia after clinical assessment. It lists specific contraindications and referral situations. A calculator result alone should not be used to decide whether IV FCM is appropriate.

Important safety checks

Pregnancy: The NHM guideline states that moderate anaemia (Hb 7–9.9 g/dL) may be considered for IV iron after 13 weeks when specified conditions apply, such as oral iron intolerance, non-compliance, or inadequate Hb response. Severe anaemia at Hb <5 g/dL or severe anaemia at gestation >34 weeks requires immediate hospitalisation with specialist care according to the guideline.

Do not use the calculator result as an automatic treatment order. The NHM guideline lists contraindications including known/suspected haemoglobinopathies or haemolytic anaemia, anaemia not caused by iron deficiency, hypersensitivity to injectable iron, liver disorder such as jaundice/cirrhosis, acute cardiac failure, fever/acute illness, and serum ferritin >150 µg/L.

Administration: IV iron requires an appropriately equipped clinical setting, trained staff, observation and management capability for infusion reactions. The NHM guideline recommends post-infusion monitoring and documentation of relevant patient information and adverse events.

Government of India IV iron context

Population	Guideline context	Important qualification
Pregnant women	Moderate anaemia: Hb 7–9.9 g/dL; severe anaemia: Hb 5–6.9 g/dL at 13–34 weeks.	IV iron is for iron-deficiency anaemia and requires the specified clinical assessment/indications.
Lactating mothers	Moderate anaemia: Hb 7–9.9 g/dL; severe anaemia: Hb 5–7.9 g/dL in the guideline.	The guideline's moderate-anaemia indication refers to mothers of a 0–6 month child and specified oral-iron circumstances.
Hb <5 g/dL in pregnancy	Immediate hospitalisation is advised irrespective of gestation.	Use specialist clinical management; do not rely on calculator output.

Frequently asked questions

What formula does this FCM calculator use?

It uses the Ganzoni formula reproduced in the Government of India/NHM operational guideline: 2.4 × body weight × (target Hb − actual Hb), plus the guideline's iron-store allowance.

Which weight should be entered in pregnancy?

The NHM guideline specifies pre-pregnancy weight. If that is unavailable, it says to use the weight recorded during the first visit of the first trimester.

Why is the pregnancy target Hb set to 11 g/dL?

Annexure III of the Government of India operational guideline specifies a target Hb of 11.0 g/dL for pregnant women.

Does the calculated dose mean the patient should receive that dose?

No. It is an estimated iron requirement. Eligibility, diagnosis of iron deficiency, contraindications, product information, current laboratory results, previous iron exposure and the applicable local protocol must be assessed by the treating clinician.

Can the whole calculated FCM dose be given in one sitting?

Not automatically. The NHM guideline states a maximum FCM dose of 1,000 mg in one session. A total requirement above that needs clinician-directed planning according to the applicable protocol and product information.

Medical disclaimer: This online calculator is an educational and clinical calculation aid. It does not diagnose iron-deficiency anaemia, determine eligibility for IV iron, prescribe ferric carboxymaltose, or replace a clinician's assessment. Always follow the current Government of India/NHM guidance, applicable state/facility protocol, approved product information, and the treating clinician's decision. For severe anaemia, acute illness, suspected haemoglobinopathy, hypersensitivity, or other red flags, seek appropriate medical care rather than relying on this calculator.

References

1. Ministry of Health and Family Welfare, Government of India / National Health Mission. Operational Guidelines on Intravenous Iron Treatment in Pregnant Women and Lactating Mothers. The guideline includes Annexure III for IV iron dose calculation and Annexures covering administration, monitoring and adverse-event management.

2. World Health Organization. Medical eligibility criteria for contraceptive use, 6th ed. (2025). This is not the dosing source for FCM; it is included here only as an example of the WHO's current guideline framework for reproductive-health clinical decision-making.