Height | |
unit | cm inches |
Weight | |
unit | Kgs lbs |
Ideal body weight (IBW) has historically had several recommended methods of calculation; however, we are now in the era of Body Mass Index (BMI) and a recommended formula based upon this has been proposed.
IBW (kgs) = 22 x (height in meters) 2
In obese patients, where actual body weight is >30% over calculated IBW, an Adjusted Body Weight (ABW) is often recommended for drug dosing.
ABW=IBW+0.4(actual weight-IBW)
Historical formulas for IBW have included:
Devine Formula:
Males: 50 kg + 2.3 kg for each inch over 5 ft
Females: 45.5 kg + 2.3 kg for each inch over 5 ft
Robinson Formula:
Males: 52 kgs + 1.9 kg for each inch over 5 ft
Females: 49 kgs + 1.7 kgs for each inch over 5 ft
Miller Formula:
Males: 56.2 kgs + 1.41 kgs for each inch over 5 ft
Women: 53.1 kgs + 1.36 kgs for each inch over 5 ft
References:
Lemmens HJ, et al. Estimating Ideal Body Weight - A New Formula. Obesity Surgery. 2005 August;15(7):1082-3.
Robinson JD, et al. Determination of ideal body weight for drug dosage calculations. Am J Hosp Pharm. 1983;40:1016-9.