Formula used for estimation of the total iron requirement is

(4.4 x body weight (kg) x Hb deficit (g/dl) (269-Dutta 6th) (549-KDT)Estimation of the total requirement* 0.3 x W (100-Hb%) mg of elemental iron, where W= patients weight in pounds, Hb% = observed haemoglobin concentration in percentage. Additional 50% as to be added for partial replenishment of the body store iron.Examples - The total requirement of iron in anaemic patients weighing 100 lb with haemoglobin 50% is calculated as follows 0.3 x 100 (100-50) = 3/10 x 100 x 50 = 1500. Add 50% = 750 mg. Total iron requirement = 2250 mg.Iron requirement (mg) = 4.4 x body weight (kg) X Hb deficit (g/dl)