Creatinine clearance (CrCl)
Cockcroft-Gault equation — renal function for drug dose adjustment.
Cockcroft-Gault formula
CrCl = [(140 − age) × weight] / [72 × SCr] × F
F = 0.85 if female · weight in kg · SCr in mg/dL · result in mL/min
Original reference: Cockcroft & Gault, Nephron 1976. FDA dose-adjustment guidance: FDA renal impairment guidance (PDF). eGFR comparison: KDOQI GFR calculator.
Frequently asked questions
What is the Cockcroft-Gault equation?
Cockcroft-Gault (1976): CrCl = [(140 − age) × weight] / [72 × SCr] × 0.85 (female). Original publication: Cockcroft & Gault, Nephron 1976. FDA recommends Cockcroft-Gault for renal dose adjustment per the FDA renal impairment guidance.
CrCl vs eGFR — which should I use for drug dosing?
Most FDA drug labels use CrCl (Cockcroft-Gault) for dose adjustments. eGFR (CKD-EPI) is used for CKD staging. A 2023 FDA/NIDDK workshop recommended re-evaluating this — see FDA renal impairment guidance and the KDOQI eGFR calculator for comparison.
What weight should be used in Cockcroft-Gault for obese patients?
Use actual weight if ABW ≤ IBW. For obese patients (ABW > IBW), use IBW or AdjBW — the appropriate weight is drug- and guideline-specific. See FDA renal impairment guidance and PMC dosing in obesity. Use the BMI & body weight calculator to estimate IBW and AdjBW.