
Ganzoni Formula
Ganzoni formula is used to calculate the Total Iron Deficit to achieve required Hemoglobin levels.
BMI = body mass index; Hb = hemoglobin.
- Total iron deficit (mg) = Weight in kg x (Target Hb – Actual Hb in g/dL) x 2.4 + Iron stores.
- Ideal body weight should be used for obese patients, e.g., by calculating weight at BMI.
- Default target Hb is 12 g/dL. Lower Hb targets may be appropriate based on clinical judgment.
- 2.4 = 0.0034 × 0.07 × 10,000, where 0.0034 is the iron content of Hb, 0.07 is blood volume based on 7% of body weight, and 10,000 is the conversion factor from g/dL to mg/L.
- For patients above 35 kg, iron stores are at least 500 mg, the lower limit of normal for small women. Some guidelines use 10 mg to 15 mg iron/kg body weight while others use 1,000 mg iron for stores.
Reference: https://www.ncbi.nlm.nih.gov/books/NBK564172/table/pe.app5.tab4/