Iron Deficit (Ganzoni Equation)

Calculates the total body iron deficit (mg) required to restore haemoglobin to target levels and replenish iron stores, commonly used for dosing intravenous iron formulations (e.g., Monofer, Ferinject).

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Formula: Weight(kg) x (Target Hb - Actual Hb)(g/dL) x 2.4 + Depot Iron(mg)

Body Weight (kg)

Haemoglobin Unit

Actual Hb

Target Hb

Usually 15 g/dL (150 g/L) for <35kg, or 13-15 g/dL otherwise.

Depot Iron Store (mg)

Results

Total Iron Deficit

mg of Iron

Note: Dosing is usually rounded up to the nearest vial size (e.g., 500mg or 1000mg depending on product characteristics). Consult the specific SPC (e.g., Ferinject simplified dosing table vs Ganzoni) as many modern IV irons prefer simplified dosing grids over this equation for adults.

Formula

Deficit (mg) =
Weight (kg) ×
(Target Hb - Actual Hb) × 2.4
+ Depot Iron (mg)

Note on units: The constant 2.4 requires Hb to be in g/dL. If Hb is provided in g/L, it must be divided by 10 before calculation. (e.g., 100 g/L = 10 g/dL).

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