Endocrinology and metabolism
Ideal Body Weight (IBW)
Devised by Devine for medication dosing.
Ideal Body Weight (IBW) calculator
Result
65.9kg
Adjusted BW (if obese) ≈ IBW + 0.4×(ABW−IBW)
Devine formula. Aminoglycosides, LMWH, ventilator tidal volume use IBW.
How to use it
- 1
Devine formula. Male: 50 + 2.3 kg per inch over 5 ft. Female: 45.5 + 2.3 per inch over 5 ft.
- 2
Adjusted body weight (AdjBW) for obese patients. AdjBW = IBW + 0.4 × (ActualBW − IBW).
- 3
Ventilation. Tidal volume for mechanical ventilation = 6 mL/kg × IBW.
When to use it
- Mechanical ventilation
- Lung-protective tidal volume based on IBW, NOT actual body weight.
- Aminoglycoside dosing
- Amikacin, gentamicin: mg/kg IBW (or AdjBW if obese).
- LMWH dosing
- Enoxaparin: cap at 144 mg/day in severe obesity; some centres use AdjBW.
A reference for clinicians and students, not medical advice. A score supports a decision; it does not make one. Check every result against the patient in front of you and your local protocol.
At a glance
- Specialty
- Endocrinology and metabolism
- Inputs
- 2
- Type
- Formula
