Ideal Body Weight (Devine) & Adjusted Body Weight (AdjBW) Calculator
Calculates Ideal Body Weight (IBW) and 40%-corrected Adjusted Body Weight (AdjBW) for hydrophilic drug dosing (e.g., aminoglycosides) in obesity.
⚠️ Educational Calculation & Clinical Safety Safeguard: Use IBW for acyclovir/theophylline and AdjBW (when TBW > 1.2 × IBW) for aminoglycosides. Educational calculations do not replace clinician assessment, patient-specific laboratory monitoring, or institutional prescribing protocols.
Interactive Calculator
Allowed physiological/compounding range: 140 to 230 cm
Allowed physiological/compounding range: 30 to 300 kg
Allowed physiological/compounding range: 0 to 1 1=Male, 0=Female
Calculated Output (kg (IBW & AdjBW))
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Step-by-Step Mathematical Derivation & Explanation:
Validated Formula & Conversion Rules
Height (in) = cm / 2.54; IBW (Male) = 50 + 2.3×(in − 60); IBW (Female) = 45.5 + 2.3×(in − 60); AdjBW = IBW + 0.4 × (TBW − IBW)Worked Clinical Example
Male, 170 cm (66.93 in), Actual Weight 95 kg: IBW = 50 + 2.3 × 6.929 = 65.94 kg; AdjBW = 65.94 + 0.4 × (95 − 65.94) = 77.56 kg.
Rounding Rules, Clinical Interpretation, Assumptions & Known Limitations
- 1. Purpose: Calculates Ideal Body Weight (IBW) and 40%-corrected Adjusted Body Weight (AdjBW) for hydrophilic drug dosing (e.g., aminoglycosides) in obesity.
- 2. Required Inputs & Validated Units: Patient Height (≥152.4 cm / 60 in) (cm, range 140–230), Actual Body Weight (TBW) (kg, range 30–300), Biological Sex (1 = Male, 0 = Female) (1=Male, 0=Female, range 0–1)
- 3. Output Unit:
kg (IBW & AdjBW) - 4. Result Interpretation Notes: Calculates Devine Ideal Body Weight (IBW) and 40%-corrected Adjusted Body Weight (AdjBW) for obese patients.
- 5. Rounding Guidance: Round dosing weights to 1 decimal place (kg).
- 6. Mathematical & Clinical Assumptions: Devine equation is calibrated for adults >= 60 inches (152.4 cm) tall.
- 7. Known Limitations & Contraindications to Formula Use: Use IBW for highly hydrophilic drugs with restricted adipose distribution (e.g., acyclovir, neuromuscular blockers) and AdjBW for aminoglycosides.
- 8. Supporting Compendial & Clinical References: Indian Pharmacopoeia (IP 2022), National Formulary of India (NFI), British National Formulary (BNF), and NCBI Bookshelf Clinical Pharmacology Compendia.