Creatinine clearance (Cockcroft–Gault)
Work out the kidney number that doctors and pharmacists use to set the dose of some medicines.
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What the numbers mean
| Creatinine clearance | eGFR | |
|---|---|---|
| Formula | Cockcroft–Gault (1976) | CKD-EPI (2021) |
| Uses | Age, weight, sex and creatinine | Age, sex and creatinine |
| Unit | mL/min | mL/min/1.73 m² |
| Used for | Setting medicine doses | Judging kidney health |
Creatinine clearance = (140 − age) × weight in kg ÷ (72 × creatinine in mg/dL), × 0.85 for women.
When to see a doctor
- You have kidney disease and are starting a new medicine: ask whether the dose needs changing.
- Your creatinine is above the normal range on your report, or higher than before.
- You think the dose of a medicine may need changing: ask your doctor or pharmacist, and never change it yourself.
Talk to a doctor
Bring your numbers to your visit. Our doctors will explain what they mean for you and what to do next.
This tool is a guide, not a diagnosis; your doctor’s advice comes first. Nothing you type leaves your device.