Creatinine Clearance
—
mL/min
Drug dosing using CrCl must follow local formulary or specialist pharmacy guidance.
This tool is for educational and learning purposes only.
Worked Example
Given: Age 72 years, Female, Weight 58 kg, Serum creatinine 1.4 mg/dL
Formula: CrCl = ((140 − 72) × 58) / (72 × 1.4)
Calculation: (68 × 58) / 100.8 = 3944 / 100.8 ≈ 39.1 mL/min
Female correction: 39.1 × 0.85 = 33.2 mL/min
Interpretation: Moderately reduced renal function (30–59 mL/min). Relevant for drugs requiring renal dose adjustment.
Classification (Educational Bands)
≥ 90 mL/min
Normal / High
60–89 mL/min
Mildly reduced
30–59 mL/min
Moderately reduced
15–29 mL/min
Severely reduced
< 15 mL/min
Kidney failure range
These bands are for educational orientation. Clinical staging uses CKD-EPI eGFR with context.
Clinical Notes
- Cockcroft–Gault estimates CrCl, not GFR — the two are numerically similar but conceptually distinct.
- Many drug datasheets specify dosing by CrCl using this equation.
- The 0.85 female correction accounts for lower average muscle mass.
- Ideal body weight or adjusted body weight may be used in obesity — follow local guidelines.
Less reliable in: extremes of body size, pregnancy, unstable renal function,
acute kidney injury, amputees, severe muscle wasting, and rapidly changing creatinine.
Consult senior or pharmacy for drug dosing in these situations.
CrCl vs eGFR: Cockcroft–Gault CrCl is commonly used for drug dosing.
CKD-EPI eGFR is used for CKD staging and is reported by most laboratories.
They are not interchangeable.
References
- Cockcroft DW, Gault MH. Prediction of creatinine clearance from serum creatinine. Nephron. 1976;16(1):31–41.
- Levey AS et al. A more accurate method to estimate glomerular filtration rate from serum creatinine. Ann Intern Med. 2009;150(9):604–612.