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Ideal Body Weight (IBW)
Devine and Robinson formulas for weight-based drug dosing reference
Devine Formula
—
kg
Robinson Formula
—
kg
Height: — cm = — inches
IBW Formulas
| Formula | Male | Female |
|---|---|---|
| Devine (1974) | 50 + 2.3 × (in − 60) | 45.5 + 2.3 × (in − 60) |
| Robinson (1983) | 52 + 1.9 × (in − 60) | 49 + 1.7 × (in − 60) |
Height in inches = Height (cm) / 2.54
Devine: Male = 50 + 2.3 × (inches − 60) | Female = 45.5 + 2.3 × (inches − 60)
Robinson: Male = 52 + 1.9 × (inches − 60) | Female = 49 + 1.7 × (inches − 60)
Devine: Male = 50 + 2.3 × (inches − 60) | Female = 45.5 + 2.3 × (inches − 60)
Robinson: Male = 52 + 1.9 × (inches − 60) | Female = 49 + 1.7 × (inches − 60)
Drug Dosing Rule: Use IBW for aminoglycosides (gentamicin, tobramycin), digoxin, heparin (some protocols), and low-molecular-weight heparins. If actual body weight < IBW → use actual body weight. For obese patients (actual > 130% IBW) → consider Adjusted Body Weight (ABW).
For clinical decision support only. Not a substitute for professional medical judgment.
